On Tuesday, voters in four separate states will head to the polls as the strength of the GOP establishment in Washington is tested against grassroots “Make America Great Again” conservative economic nationalist candidates.

Voters in West Virginia, Ohio, North Carolina, and Indiana will select their nominees to represent their respective parties for a variety of different offices, from House races to Senate nominations to governor’s races–and much of what happens in these states will set the tone for what is to come in upcoming races elsewhere around the country.

President Donald Trump won each of these four states in the general election in 2016 against Democrat Hillary Rodham Clinton as he swept the country with 30-and-a-half states and 306 electoral votes. In the primaries in 2016, he won three of the four–losing only Ohio to favorite son and outgoing Gov. John Kasich.

Here is a breakdown of what to look for in many of the competitive races on Tuesday night as results flow in from across these four states.

West Virginia Senate Primary

This state’s senate race has become surprisingly competitive in the final week or so, with former Massey Energy CEO Don Blankenship surging in the final analysis. Despite his conviction and prison sentence–and his claims in court to no longer be a resident of West Virginia as far back as several years ago–this Las Vegas, Nevada, resident has boosted his candidacy for the GOP nomination in West Virginia’s senate race by blasting Senate Majority Leader Mitch McConnell.

Blankenship’s racy ads have skyrocketed his candidacy to national prominence–earning him scorn from basically everyone in the GOP and the entire national media. Republicans are concerned that a once-thought-to-be-easily-winnable race against incumbent Sen. Joe Manchin (D-WV) may be lost should Blankenship succeed in pulling in the nomination.

It is only private polls that have Blankenship winning, and public polling has Attorney General Patrick Morrisey–a true supporter of President Trump and his agenda–in front. Depending on which polling is right, a Morrisey win would be a win for Republicans.

But it’s not that simple as a head-to-head between Morrisey and Blankenship, which Morrisey would probably win. McConnell and his forces in Washington, D.C., are heavily backing former Democrat and one-time Hillary Rodham Clinton-for-president backer Rep. Evan Jenkins (R-WV) for the nomination. Jenkins, who did not switch parties until after the end of Barack Obama’s first term in the White House, supported Clinton for president in 2008 before switching to the GOP in 2013. McConnell and his allies are pushing extraordinarily hard for Jenkins.

President Trump, meanwhile, is urging West Virginians to back either Morrisey or Jenkins–despite false claims from Jenkins that he was endorsed by President Trump–in order to stop Blankenship:

This one will surely be a photo finish, and whatever happens in this race will say a lot about upcoming races–and GOP prospects for keeping or adding to their slim majority in the U.S. Senate moving forward.

West Virginia’s Third Congressional District

This race will also say a lot about the future of the GOP. For two decades before Jenkins was elected to this seat–he’s giving it up to run for the Senate seat–the third district in West Virginia was represented by former Democrat Rep. Nick Rahall (D-WV). Jenkins, while now a Republican, is a former Democrat and would be described as an “establishment Republican” at best. So while Republicans are aiming to hold onto the seat that they picked up in the 2014 midterm elections for the first time in decades, there is also an opportunity to get a “better Republican” than Jenkins to be the nominee on Tuesday.

There are two candidates, per GOP sources in the state, with an actual chance of winning the nomination: former state party chairman Conrad Lucas–an ardent supporter of President Trump and his agenda who has made multiple appearances on Breitbart News radio on SiriusXM 125 the Patriot Channel–and West Virginia House of Delegates member Carol Miller.

When Lucas was on Breitbart News Saturday this weekend, he hit Miller for backing tax increases in the West Virginia state house. If Republicans in the district are ready for a stronger Republican, they will likely nominate Lucas. But if they want more of the same, then Miller will likely get the nod. It remains to be seen what will happen here, and this one is expected to be a photo finish as well.

Indiana Senate Primary

The race to face off against red state Democrat Sen. Joe Donnelly (D-IN) in Indiana is a fierce one, where all three candidates have aggressively positioned themselves as the pro-Trump Republican. Reps. Todd Rokita (R-IN) and Luke Messer (R-IN) and businessman and former state Rep. Mike Braun will face the voters in Indiana’s primary on Tuesday.

Indiana is an interesting state, as it is where former Gov. Mike Pence–Trump’s Vice President–hails from and it is also the state where Trump wrapped his historic whirlwind across the country, stunning the political class and media to win the GOP nomination for president. One may remember that Pence, at the time the governor of Indiana, sort of backed Sen. Ted Cruz (R-TX) ahead of that final primary, saying he personally was voting for Cruz but that it was not an attack on Trump. Trump later selected Pence as his running mate, helping him win the White House against Clinton.

Rokita. Messer, and Braun have each made appealing to Trump supporters the core of their campaign message.

Rokita, in addition to appearing multiple times on Breitbart News radio to make the case for English as the official language of the United States, is running this ad in Indiana in the closing days:

Messer, meanwhile, has led a push to formally nominate President Trump for the Nobel Peace Prize for his work in getting North Korea to denuclearize–something presidents for decades have tried but failed to do. Messer has also appeared on Breitbart News radio multiple times.

Braun, who has refused to appear on Breitbart News radio despite multiple invitations to do so, is running this ad focused on putting America first–before China and Mexico:

Ohio Gubernatorial Primary

The attorney general of Ohio, Mike DeWine, has had an edge in that race for months, but Lt. Gov. Mary Taylor has seen a late surge behind her campaign. DeWine, a former U.S. Senator, has come under serious fire from conservatives about a fundraiser he had with Islamic leaders during his time in the U.S. Senate. He has also come under scrutiny for his record on immigration.

Taylor, meanwhile, has earned endorsements from Sens. Ted Cruz (R-TX) and Rand Paul (R-KY) and from the American Conservative Union–while DeWine battles allegations that he is not conservative or pro-Trump enough for the job.

It’s a bit of an uphill climb for Taylor in the end, as the last public polls had her down close to double-digits. But private polling, Ohio sources say, has her a lot closer–and DeWine and his running mate have spent the past several days barnstorming the state as part of their self-described “Rock Solid Conservative” tou, while blanketing Ohio with a million-dollar ad buy claiming they are the pro-Trump ticket.

It’s anybody’s game in Ohio, but if Taylor pulls off an upset and defeats DeWine on Tuesday, it won’t be a good sign for the GOP establishment nationall as these battles with grassroots candidates continue heading into other states.

Ohio House Races

There are two GOP primary House races in particular worth watching out of the Buckeye State, specifically Ohio’s 12th district and Ohio’s 16th district. In both places, strong pro-Trump women are angling to defeat GOP establishment-backed men in their primaries.

In the 12th, Melanie Leneghan is running this ad portraying herself as the “real” “Trump conservative”:

And this one targeting her opponent state Sen. Troy Balderson:

Leneghan is a businesswoman, and by focusing her campaign on backing Trump–and with an endorsement from founding House Freedom Caucus chair Rep. Jim Jordan (R-OH)–she has a real chance to defeat the establishment on Tuesday.

Over in the 16th district, 29-year-old Christina Hagan is running against GOP establishment-backed Anthony Gonzalez. Hagan is easily the most “America First” candidate in the country, but she’s got an uphill battle against Gonzalez–a former NFL star–and his deep pockets. Breitbart News’s own John Binder is in Ohio with Hagan, and reported a deep profile on her campaign here.

But here is a video of Hagan on Tucker Carlson Tonight on Fox News on Monday night, the night before the election, in which she made the case for ending foreign aid to Mexico until the country stops sending millions of illegal aliens and drugs into the United States:

North Carolina’s 9th District

Down in North Carolina’s 9th congressional district, incumbent Rep. Robert Pittenger (R-NC) is in the fight of his political life against Dr. Mark Harris–a conservative pro-Trump challenger who nearly beat him last go-around. Pittenger only beat Harris in the 2016 primary in the same district a couple years ago by 134 votes, and he faces Harris again on Tuesday for a re-match.

Harris has focused his campaign on hammering Pittenger for being a part of the “swamp” and for voting for the omnibus spending bill that hiked spending–under a GOP-led Congress–to more than $1.3 trillion over the next year. The bill, which does not fund President Trumo’s border wall, has landed Pittenger in hot water back home in North Carolina as Harris races around the district beating him up for voting for it.

Pittenger, for his part, has taken great pains to make sure he portrays himself as sufficiently pro-Trump. McClatchy’s Katie Glueck reported from North Carolina toward the end of April in a feature piece on the race.:

Congressman Robert Pittenger couldn’t go 30 seconds without mentioning President Donald Trump. At a church 5K run and a local Republican convention, an early voting station and a panel discussion hosted by a pro-Trump group, the GOP congressman in the midst of a primary battle typically waited between five and 30 seconds before invoking the president as he campaigned last weekend—and often, the favorable comparisons to iconic conservative President Ronald Reagan weren’t far behind. It was a constant reminder of the lengths Republican candidates are going to embrace Trump this primary season, from here in Pittenger’s district to Senate races in West Virginia, Ohio and Indiana, all places where primary Election Day comes May 8. It’s more evidence of the president’s grip on the GOP base—and of the perils facing any Republican candidate in a conservative area who is perceived as insufficiently supportive of Trump.

It remains to be seen which one of these two will win this second round, but it surely will be another close one.

North Carolina’s 3rd District

In this case, the incumbent Rep. Walter Jones (R-NC) is the pro-Trump conservative. Jones, a veteran conservative rabble-rouser in Congress with a history of mucking up the establishment’s best-laid plans, has a long and storied background coming from the same Pat Buchanan-wing of the GOP that Trump hails from. He opposes pointless, endless wars, backs reductions in immigration to the United States, and regularly questions trade deals as well as the out-of-control national debt.

It seems like because of Jones’s effectiveness in the House of Representatives, the GOP establishment in Washington always tries to fund a primary challenge to him–and always loses in the end. This time around, it’s Scott Dacey whm the GOP establishment in Washington, D.C., is supporting. Dacey, whose ties as a registered lobbyist in Washington, D.C. and Wisconsin connect him closely with some of the GOP establishment’s worst villains, has come under serious fire in the district from Jones–who was, as Breitbart News reported back in February, out early with critical attacks on the establishment candidate.

In an interview on Breitbart News radio in February about his race, and specifically about radio ads he was hitting Dacey with, Jones hammered the swamp in Washington, D.C.

“I’m independent,” Jones said. “I’m a conservative. I’m concerned about the future of America and I would tell you when you look at the influence on the policy whether it be the Democrats in charge or the Republicans in charge, who governs with the policies of America? It’s the special interests. We want to send, at least North Carolina does not—I hope they do not—want to send a person who came out of the swamp now wants to say they’re going to go up there and represent the average people of eastern North Carolina. In my heart, I just don’t believe it’s true. If we’re going to continue, and you probably know this Matt but I’m going to be very quick, this came out from Fox two years ago. Lobbying Congress in 1986, $61 million was spent—an average of $113,000 per lawmaker. Matt, in 2016, $3.1 billion was spent—an average of $5.8 million per lawmaker. And you want to send a lobbyist who is part of buying votes to Washington, DC? I would think not. I am a strong advocate of reform. I am seeing what has happened is that Congress is bought and paid for by the special interests.”

Here’s the full interview with Jones:

Some late-breaking reports in the past couple days claim that former House Speaker John Boehner is funding efforts to back Dacey. It’s unclear if those are confirmed or not, but the accusation has been making the rounds in conservative blogs in North Carolina for a few days. Given that Jones is an incumbent, and has held back the wrath of the GOP establishment in primaries multiple times before, he’s the odds-on favorite to defeat anti-Trump lobbyist Scott Dacey on Tuesday. But given the full-on onslaught from the establishment, we may be in for a shocker here.

There could be deeper issues here for GOP leadership in the House though, as it’s generally viewed as a bridge too far to target incumbent House members in primaries with the full might of leadership operations, and if current House Speaker Paul Ryan is at all connected into what his predecessor Boehner is reportedly doing down in North Carolina, it could be seriously problematic for conservative relations with leadership moving forward.