Today, voters in Indiana, North Carolina, Ohio, and West Virginia will go to the polls as primary season swings into high gear.

Republicans will choose Senate nominees to take on three vulnerable Democratic incumbents: Indiana's Joe Donnelly, Ohio's Sherrod Brown, and West Virginia's Joe Manchin. Both sides also have competitive races to succeed termed-out Gov. John Kasich in Ohio, as well as plenty of House races to watch across these four states.

It only takes a simple plurality to win nomination in Indiana, Ohio, and West Virginia, while North Carolina requires a July runoff if no candidate takes more than 30 percent of the vote. However, since all of the primaries we'll be watching have no more than three candidates running, all of these nominations will be settled on Tuesday, barring the most extraordinary of circumstances.

Things kick off at 6 PM ET when polls close in most of Indiana, with the small portion of the state in the Central time zone closing an hour later. Polls close in North Carolina, Ohio, and West Virginia at 7:30 PM ET.

INDIANA

● IN-Sen (D): Sen. Joe Donnelly is a vulnerable Democrat on everyone's list, but it's anyone's guess who will face him in the fall. Republicans long expected a nasty duel between Rep. Luke Messer, who is close to the state party establishment, and Rep. Todd Rokita, a former secretary of state who has always been more of a lone wolf. But wealthy former state Rep. Mike Braun has scrambled things, and he's used his fortune to outspend both congressmen and run ad after ad portraying himself as a political outsider. Polling has been scarce, so there's no telling how this one will go.

All three Republicans attracted some bad press throughout the campaign and even into the final days. Rokita has been the most aggressive about portraying himself as the one true Trump ally in the race, so it didn't look so good when Trump's re-election campaign demanded that he stop using yard signs that seemed to suggest the White House was supporting Rokita's bid. (After initially snarking, "We not not comment on yard sign strategy," the Rokita campaign appeared to cover up the bogus endorsement with painter's tape.)

Messer, meanwhile, has been on the defensive for months since news broke that he co-owns his Indiana residence with his mother while his family now lives in the D.C. area. (Similar charges that he'd "gone Washington" famously sank Sen. Richard Lugar in his 2012 primary.) Late in the race, the public also learned that in 2003, when Messer was persuading local Indiana GOP leaders to appoint him to replace a state representative who had been killed by a drunk driver, Messer had kept his own two DUIs a secret.

And finally, it turns out that Braun consistently voted in the Democratic primary until 2012, naturally leading his rivals to question his loyalty to the GOP. Braun has argued that he's a successful businessman, but a recent Associated Press article painted him in a very different light, finding that his company has been charged with a litany of labor law violations and has sought the very sort of government subsidies that Braun has attacked on the campaign trail.

● IN-02 (D) (59-36 Trump, 56-42 Romney): While GOP Rep. Jackie Walorski decisively won re-election in 2014 and 2016, Democrats haven't forgotten about her surprisingly tight 49-48 victory when she won her first term in 2012. The DCCC is hoping to target Walorski in the fall, and healthcare executive Mel Hall appears to be the frontrunner to take her on. Hall's main primary foe is businessman Yatish Joshi, who has the support of Joe Kernan, a former mayor of South Bend and Indiana's most recent Democratic governor. Hall outspent Joshi by a wide $233,000 to $59,000 from April 1-18, which the FEC calls the "pre-primary period."

● IN-04 (R) (64-30 Trump, 61-37 Romney): Rep. Todd Rokita is leaving to run for the Senate, and the winner of the crowded GOP primary should have little trouble holding this seat, which includes Lafayette and some of Indianapolis' western suburbs. The frontrunners appear to be Diego Morales, who served as a senior advisor to then-Gov. Mike Pence, and Steve Braun, who resigned as state Department of Workforce Development director to run here. (Yes you've read that name before in this piece, Braun is also a brother of Senate candidate Mike Braun, though the two haven't campaigned together.) State Rep. Jim Baird, an Army veteran who lost his left arm in Vietnam, is also in the mix.

Morales has the support of some old Pence allies (the vice president has formally remained neutral), but he drew bad headlines in March when the Journal & Courier reported that he'd left several government jobs for poor performance and seemed to exaggerate his resume. Braun, who has done some considerable self-funding, outspent Baird $321,000 to $73,000 during the pre-primary period, while Morales spent $64,000.

A pro-Morales group called With Honor Fund has aired ads hitting Braun, while the pro-Braun Citizens for a Strong America has spent at least $300,000 attacking Morales and $18,000 against Baird. Morales, a Guatemalan immigrant, took umbrage with a CSA mailer encouraging voters to send him "back across town, where he actually lives!", while another one charging that a gas tax Baird voted for cost Indiana a proverbial arm and a leg generated plenty of news coverage and condemnation.

● IN-06 (R) (68-27 Trump, 60-37 Romney): GOP Rep. Luke Messer is leaving his eastern Indiana seat to run for the Senate, and there's one undisputed frontrunner in the primary to succeed him. Businessman Greg Pence, an older brother of Vice President Mike Pence and a close Messer ally, has benefited from his family's name recognition and connections, and he's mostly cleared the field. Pence has earned some negative attention both for staying largely out of sight on the campaign trail and for some serious business failures, but it's unlikely to be enough to stop him. Pence's most visible primary foe is self-funding businessman Jonathan Lamb, who has run some truly bizarre ads (They're on youtube check'em out).

● IN-09 (D) (61-34 Trump, 57-41 Romney): Democrats hope that freshman Rep. Trey Hollingsworth's very weak ties to the state and unimpressive fundraising will give them an opening in this southern Indiana seat. The two main Democrats competing to face him are Indiana University professor Liz Watson, who previously served as a senior Democratic staffer on the U.S. House's Committee on Education and the Workforce, and civil rights attorney Dan Canon. EMILY's List is backing Watson, who outspent Cannon $89,000 to $20,000 during the pre-primary period.

NORTH CAROLINA

● NC-02 (D): (53-44 Trump, 56-43 Romney): Democrats are planning to target GOP Rep. George Holding in this suburban Raleigh seat. Tech executive Ken Romley, who has been self-funding much of his campaign, outspent former state Rep. Linda Coleman $254,000 to $34,000 during the pre-primary period. But Coleman, who lost competitive general elections for lieutenant governor in 2012 and 2016, likely began the race with considerably more name-recognition than Romley. In addition, in primaries so far in Texas and Illinois, we've generally seen women candidates performing well this cycle; if this pattern continues, it could help Coleman offset Romley's considerable spending edge. Army veteran Wendy May, who would be the first transgender member of Congress, is also in, but she hasn't reported raising anything.

● NC-03 (R): 61-37 Trump, 58-41 Romney): Twelve-term Republican Rep. Walter Jones has spent years voting against the House leadership's priorities, and now he's turned hostile to Trump's policies: This Congress alone, the self-described "thorn in people's ass" voted against the House version of Trumpcare and the tax bill, arguing that both were fiscally irresponsible. Jones faces a primary challenge from Craven County Commissioner Scott Dacey, who is arguing that this coastal seat needs a more reliable Trump ally.

Dacey outspent Jones $120,000 to $39,000 during the pre-primary period, and a mystery group called the Conservative Leadership Alliance began airing ads against Jones last month. But Jones, who announced during the campaign that he wouldn't seek another term in 2020, has won more than his fair share of competitive primaries. Marine veteran Phil Law, who lost to Jones 65-20 in 2016, is running again, and he could split the anti-incumbent vote. The only poll we've seen was a late March survey from the conservative think-tank Civitas and conducted by an arm of SurveyUSA that gave Jones a 37-28 lead over Dacey, with Law at 15.

● NC-09 (R) (54-43 Trump, 55-44 Romney): Last cycle, Rep. Robert Pittenger won a three-way GOP primary with pastor Mark Harris by just a 35.0-34.5 margin. Pittenger was running for a redrawn seat that largely new to him while also facing an FBI and IRS investigation related to his old real estate company over loans he made to his 2012 congressional campaign. Harris is seeking a rematch, but now that the investigation has ended without charges and redistricting won't be the same factor, Pittenger looks like he's in much better shape this time around in this suburban Charlotte seat.

A March poll from SurveyUSA for the conservative Civitas Institute found Pittenger ahead 52-20, with little-known candidate Clarence Goins at 7. Pittenger's campaign later released its own poll giving him a 59-26 edge, while even Harris' own survey found the incumbent up 38-30. Pittenger outspent Harris $117,000 to $64,000 during the pre-primary period, and he's aired many ads arguing that Harris opposed Trump in 2016. Whoever wins will quickly need to prepare for an expensive general election with solar energy businessman Dan McCready, who faces only a weak opponent in the Democratic primary.

OHIO

● OH-Sen (R): Two wealthy Republicans are competing to take on Democratic Sen. Sherrod Brown, but Rep. Jim Renacci is the heavy favorite. Renacci picked up an endorsement from Donald Trump late in the race, while businessman Mike Gibbons never seemed to impress party leaders. What little polling there is has found that neither candidate is very well-known, but it would be a big surprise if Renacci loses to Gibbons, who doesn't seem to have much of a base of support to draw from.

● OH-Gov (R & D): Republican incumbent and Trump critic John Kasich is termed out, and both parties have primaries to succeed him. On the GOP side, Attorney General Mike DeWine has the support of much of the party establishment over Lt. Gov. Mary Taylor, and he's also outspent her. Taylor has attacked DeWine, who served 12 years in the U.S. Senate, as a member of that dreaded establishment. DeWine and his allies have spent heavily on the airwaves to hit Taylor, so they're at least taking her seriously. But what little polling we've seen has shown DeWine consistently ahead by sizable margins, and it would be a huge upset if Taylor beat him.

The Democratic frontrunner is Richard Cordray, who narrowly lost re-election as attorney general to DeWine in 2010 and resigned in the fall as head of the federal Consumer Financial Protection Bureau to run for governor. His main opponent is former Rep. Dennis Kucinich, a longtime Cleveland politician and quixotic two-time presidential candidate. (Also a top ten member for one of your editors)

Cordray has the support of Massachusetts Sen. Elizabeth Warren (who first proposed the creation of the CFPB) and much of the state Democratic establishment, while Kucinich is relying on his old Cleveland base and several Bernie Sanders allies, though Sanders himself has remained neutral. State Sen. Joe Schiavoni never gained much traction, but he could do well in his Youngstown base; former state Supreme Court Justice Bill O'Neill is also running.

Cordray has a huge financial edge over Kucinich, but the former congressman got some last-minute help when a super PAC run by a Republican donor friendly with Kucinich ran a flight of ads hitting Cordray from the left. Still, a Kucinich win would be an upset, though it's something we can't rule out. Kucinich touted his longtime support for Medicare for all and has hit Cordray for his past A-ratings from the NRA, and even Cordray's allies concede he's not an exciting speaker.

Polling has been light here, but the last couple of surveys have given Cordray double-digit leads, albeit with large numbers of undecideds.

● OH-12 (R & D) (53-42 Trump, 54-44 Romney): GOP Rep. Pat Tiberi resigned to take a job leading an industry lobbying group, and that's created a bit of an odd situation in this suburban Columbus seat. There will be an Aug. 7 special election to complete the final months of Tiberi's term, but the primary for both the special election and the regular two-year term will take place simultaneously on Tuesday. As a consequence, there's always a small chance that someone could win their party's nomination for just one of the two contests.

The crowded GOP primary has turned into a classic establishment vs. insurgent battle. Defending Main Street, a super PAC set up to stop anti-establishment candidates from winning GOP primaries, has spent at least $400,000 on ads for state Sen. Troy Balderson. And Tiberi's used the remaining funds in his campaign account to air ads staring the former congressman praising Balderson.

On the other side, the House Freedom Caucus' allied House Freedom Action group has been spending for Liberty Township Trustee Melanie Leneghan. The anti-tax Club for Growth hasn't formally taken sides, but they've been airing ads hitting Balderson and have said they'd be happy with Leneghan.

The only poll we've seen was a mid-April Balderson poll that showed him leading Leneghan 17-11, with economist Tim Kane and state Sen. Kevin Bacon at 10, while Delaware County Prosecutor Carol O'Brien was at 7; Bacon and O'Brien seem more establishment-oriented, while the Club for Growth also said it was comfortable with Kane. In a familiar storyline, GOP insiders privately fretted to the media a few weeks ago that Leneghan is a weak candidate who could cost them this seat in the August special.

On the Democratic side, local leaders have consolidated behind Franklin County Recorder Danny O'Connor. His main primary foe is former Franklin County Sheriff Zach Scott, who badly lost a 2015 race for mayor of Columbus to Andrew Ginther (who is supporting O'Connor) and narrowly lost renomination the next year against a candidate backed by Ginther and his allies. O'Connor only outspent Scott $36,000 to $20,000 during the pre-primary period, but he had a $121,000 to $18,000 cash-on-hand edge on April 18. Farmer John Russell, who lost a 2016 race for the state House, is also in.

● OH-16 (R) (56-39 Trump, 53-45 Romney): The GOP primary to succeed Senate candidate Jim Renacci in this very gerrymandered seat, which includes parts of the Akron, Canton, and Cleveland areas, pits the old party establishment against a more Trumpesque candidate. On the one side is Anthony Gonzalez, who was a football star at the Ohio State University and later went on to play for the Indianapolis Colts. Gonzalez has the backing of influential donors and local political figures, while the U.S. Chamber of Commerce launched a $300,000 buy for him in the final week of the campaign.

His opponent is state Rep. Christina Hagan, who was a prominent Trump backer in 2016 when Ohio Gov. John Kasich was also seeking the GOP presidential nomination. Hagan has an endorsement from the NRA as well as from two of the most prominent people to be fired from the Trump administration: Anthony Scaramucci and Sebastian Gorka. Hagan has pitched herself as a Trump ally and argued that Gonzalez, who worked in Silicon Valley before he came home to run for office, is an insider. Gonzalez outspent Hagan by a wide $272,000 to $74,000 during the pre-primary period, and most of the outside spending has been for him.

WEST VIRGINIA

● WV-Sen (R): Democratic Sen. Joe Manchin is one of the GOP's top targets in the Senate this year, and three noteworthy Republicans are competing to face him. The party establishment hasn't shown much of a preference between Rep. Evan Jenkins or Attorney General Patrick Morrisey, but they've made it very clear they view former Massey Energy CEO Don Blankenship as dangerously unelectable, and they've spent heavily to stop him. One day before the primary, Trump even tweeted that voters should support Jenkins or Morrisey but not Blankenship.

It's not hard to see why so many Republicans fear that Blankenship would be a toxic nominee. After a 2010 explosion at Massey's Upper Big Branch mine resulted in the deaths of 29 of Blankenship's employees, he spent a year in prison for conspiring to violate federal mine safety laws. While most people with such a record would gladly slink off into obscurity, not Blankenship: He declared himself a political prisoner of the Obama administration, spending millions of his own money on ads making that argument (with racist flourishes), as well as attacks on Manchin, Morrisey, and Jenkins. It's a message that could indeed work in a state like West Virginia.

The good news for Blankenship enemies like Senate Majority Leader Mitch McConnell (whom Blankenship infamously dubbed "Cocaine Mitch" in a campaign ad) is that recent public polls show him firmly in third place, while Jenkins and Morrisey are locked in a tight race. However, they're still acting worried, and private GOP polls reportedly showed Blankenship taking a small lead in the final days of the race.

And indeed, Jenkins and Morrisey have mostly been attacking one another, though Morrisey belatedly started going after Blankenship in the final weekend of the campaign. Jenkins has hit Morrisey's past work as a lobbyist, while Morrisey has gone after Jenkins for being a Democrat until he ran for Congress in 2013. Morrisey has also benefited from some outside spending from a super PAC funded by conservative mega donor Richard Uihlein. National Democrats, meanwhile, have also spent big to influence the race. While it originally looked like they were attacking both Jenkins and Morrisey equally in order to help Blankenship, Team Blue has spent almost all of its money against Jenkins while mostly leaving Morrisey alone.

● WV-02 (D) (66-29 Trump, 60-38 Romney): This central West Virginia seat is very much a longshot Democratic target, but Team Blue hopes that Rep. Alex Mooney, who, believe it or not, was a member of the Maryland legislature before joining the Mountain State's congressional delegation in 2014, could be vulnerable in a good year. Army veteran Aaron Scheinberg is facing off with former U.S. State Department official Talley Sergent in the Democratic primary. Scheinberg outspent Sergent $92,000 to $65,000 during the pre-primary period, and he had considerably more money left over. However, Scheinberg only moved to West Virginia from New York in 2017, and while he touts his family's roots in the state, he could negate Team Blue's best line of attack against the carpetbagging Mooney.

● WV-03 (R) (73-23 Trump, 65-33 Romney): Evan Jenkins' 2014 win over Democratic incumbent Nick Rahall made him the first Republican to represent southern West Virginia in generations, and there's a crowded GOP field to succeed the Senate candidate. There's no obvious frontrunner, and major outside groups also haven't taken sides here.

Del. Carol Miller outspent fellow Del. Rupie Phillips, a longtime Democrat who only became a Republican last year, $179,000 to $135,000 during the pre-primary period, while former state party chair Conrad Lucus deployed $135,000. Del. Marty Gearheart and former Del. Rick Snuffer, who lost to Rahall in 2004 and 2012, are also in, but they've spent little between them. Team Blue is hoping that this seat's old Democratic heritage could give them an opening, and a few candidates are competing for the nod. However, only state Sen. Richard Ojeda, an Iraq veteran who was brutally beaten at a campaign event in 2016, has spent much money, and he's also attracted a good deal of national attention

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