A slew of May primary battles begin Tuesday as the Republican establishment looks to reassert their control over a divided GOP in a number of states.

Its first big test comes in North Carolina, where business-friendly GOP groups have gone all-in for House Speaker Thom Tillis as he seeks to avoid a primary runoff and turn his focus to Sen. Kay HaganKay Ruthven HaganTillis trails Democratic challenger by 7 points in North Carolina poll North Carolina businessman will challenge Tillis in GOP primary Embattled senators fill coffers ahead of 2020 MORE (D-N.C.). The race is a top priority for the GOP as they seek to win back the Senate.

A win on Tuesday allows Tillis to conserve resources for the general election and train his fire on Hagan, who has had a narrow lead against Tillis in most recent public polls. But if he falls short he’ll have to slog it out for another few months, potentially hurting his chances in the general election and giving the Tea Party another shot.

In the eastern end of the state, establishment Republicans face a tough challenge in defeating Rep. Walter Jones, an iconoclastic Republican who’s been a regular thorn in the side of GOP leaders. He’s facing Taylor Griffin, a former Treasury official during George W. Bush’s administration who has backing from many establishment Republicans. Griffin has also been endorsed by former Alaska Gov. Sarah Palin (R), who he worked for while on Sen. John McCainJohn Sidney McCainFighter pilot vs. astronaut match-up in Arizona could determine control of Senate The Hill's Morning Report — Recession fears climb and markets dive — now what? Trump makes rare trip to Clinton state, hoping to win back New Hampshire MORE’s (R-Ariz.) presidential campaign.

Establishment Republicans are also fighting for their preferred candidate to replace retiring Rep. Mike McIntyre (D-N.C.) and supporting House Speaker John BoehnerJohn Andrew BoehnerLobbyists race to cash in on cannabis boom Rising star Ratcliffe faces battle to become Trump's intel chief This little engine delivers results for DC children MORE (R-Ohio) and Rep. David Joyce (R-Ohio) in their Tuesday primaries.

Democrats will narrow the field to replace former Rep. Mel Watt (D-N.C.), and former America Idol star Clay Aiken (D) will find out whether he’ll get to face Rep. Renee Ellmers (R-N.C.).

SENATE SHOWDOWN

AK-SEN (BEGICH): Republican Senate candidate Dan Sullivan has a big primary lead and trails Sen. Mark BegichMark Peter BegichAlaska political mess has legislators divided over meeting place Former GOP chairman Royce joins lobbying shop Lobbying world MORE (D-Alaska) by 44 percent to 42 percent in an internal poll obtained by The Hill.

IA-SEN (OPEN): Senate candidate Joni Ernst (R) fires on ObamaCare, and shows off her pistol skills, in her newest ad.

GA-SEN (OPEN): The Atlanta Journal-Constitution had a front-page story detailing the “rough patches” in businessman David Perdue’s (R ) career. Perdue’s business record has provided fodder for his opponents in the race.

Democrat Michelle Nunn is out with a new ad, a soft positive spot of her talking about her grandmother and her faith.

MN-SEN (FRANKEN): Sen. Al FrankenAlan (Al) Stuart FrankenNative American advocates question 2020 Democrats' commitment Reid says he wishes Franken would run for Senate again Al Franken urges Trump to give new speech after shootings: 'Try to make it sound like you're sincere, even if you're not' MORE’s (D-Minn.) main Republican opponent, Mike McFadden (R), is out with a new ad touting his frugality in an interesting way. "My dad, Mike McFadden? He's cheap,” McFadden’s son Connor says in the ad. "When I was 10 and had to get stitches out after a hockey injury, the nurse said it would cost one-hundred bucks. Dad was so horrified he grabbed the scissors and took them out himself."

MS-SEN (COCHRAN): Sen. Thad CochranWilliam (Thad) Thad CochranBiden has a lot at stake in first debate The Hill's Morning Report — Trump turns the page back to Mueller probe Trump praises Thad Cochran: 'A real senator with incredible values' MORE (R-Miss.) is facing fresh attacks from his primary challenger, state Sen. Chris McDaniel, over his commitment to Mississippi, after a report revealed Cochran listed a Washington, D.C., location as his primary address on numerous official documents.

NE-SEN (OPEN): Nebraska Republican Senate candidate Shane Osborn described his duties as state Treasurer as broader than they actually were during his time in office. The revelation may give fodder to detractors who have labeled him as “dishonest” in a recent ad because of a memo circulated by his campaign defending his Naval service. But that ad has been taken down by two stations in the state, after confronted with a letter from the Osborn campaign challenging its veracity.

NH-SEN (SHAHEEN): Sen. Jeanne ShaheenCynthia (Jeanne) Jeanne ShaheenSunday shows - Recession fears dominate Lewandowski on potential NH Senate run: If I run, 'I'm going to win' Lewandowski says he's 'happy' to testify before House panel MORE (D-N.H.) is touting her work for New Hampshire's veterans in the first ad of her campaign. Republicans, meanwhile, slammed her for failing to deliver on what they said was a 2008 campaign promise to bring a full-service veterans’ clinic to the state.

NC-SEN (HAGAN): Former presidential nominee Mitt Romney endorsed Thom Tillis’s Senate campaign, making him the latest establishment Republican to back Tillis ahead of Tuesday’s primary.

OK-SEN (OPEN): The New York Times profiled former Oklahoma House Speaker T.W. Shannon this weekend, looking at how his Chickasaw heritage could be a mixed blessing for the candidate as he seeks the Republican nomination for Senate in Oklahoma against Rep. James Lankford (R-Okla.). Meanwhile, conservative talk-radio host Hugh Hewitt endorsed Lankford in the race.

TN-SEN (ALEXANDER): State Rep. Joe Carr, the long-shot primary challenger to Sen. Lamar AlexanderAndrew (Lamar) Lamar AlexanderThe Hill's Morning Report - How will Trump be received in Dayton and El Paso? McConnell faces pressure to bring Senate back for gun legislation Criminal justice reform should extend to student financial aid MORE (R-Tenn.), filed his personal financial disclosure forms months after his August entry into the race.

WV-SEN (MANCHIN): Sen. Joe ManchinJoseph (Joe) ManchinSunday shows - Recession fears dominate Manchin: Trump has 'golden opportunity' on gun reforms Trump vows to 'always uphold the Second Amendment' amid ongoing talks on gun laws MORE (D-W.Va.) hinted Monday that he might leave the Senate and will decide at the end of this year whether to run for governor again.

BATTLE FOR THE HOUSE

POLLS SHOW GOP MIDTERM EDGE: A Pew/USA Today poll released Monday found 47 percent of registered voters support the Republican candidate in their district or lean Republican, while 43 percent favor the Democratic candidate or lean Democratic. A CNN poll also out Monday showed 46 percent of registered voters backing a Republican candidate on a generic congressional ballot, while 45 percent chose a Democrat.

DCCC PITCHING ROSIE: The Democratic Congressional Campaign Committee launched a new effort to woo unmarried women who are likely to vote Democratic, but expected not to vote during the midterms. The effort, titled Reengaging Our Sisters in Elections — or ROSIE, after the iconic feminist figure Rosie the Riveter — is part of a broader attempt to mitigate the turnout problems Democrats expect to face this fall.

PA-10 (OPEN): Former Secretary of State Hillary ClintonHillary Diane Rodham ClintonLewandowski on potential NH Senate run: If I run, 'I'm going to win' Fighter pilot vs. astronaut match-up in Arizona could determine control of Senate Progressive Democrats' turnout plans simply don't add up MORE is making her first campaign stop of 2014 for her in-laws, attending a fundraiser for former Rep. Marjorie Margolies (D-Pa.), who is seeking a comeback for her old seat after two decades out of Congress. Chelsea Clinton is married to Margolies’s son.

WV-03 (RAHALL): Rep. Nick RahallNick Joe RahallWe shouldn't allow politics to impede disaster relief Break the cycle of partisanship with infant, child health care programs Clinton mulls role in 2018 midterms MORE (D-W.Va.) is using his latest ad to tout his record supporting the coal industry and to criticize outside spending against him.

2016 WATCH

A ROMNEY REDUX? Utah State Republican Party Chairman James Evans told the Deseret News that a group of Republicans in the state are launching an effort to draft 2012 GOP presidential nominee Mitt Romney into the 2016 race.

SANTORUM ENDORSES MIN. WAGE INCREASE: Former Pennsylvania Sen. Rick Santorum broke with his party and backed a hike in the minimum wage. "Let's not make this argument that we're for the blue collar guy but we're against any minimum wage hike ever," Santorum said. "It just makes no sense."

BIDEN TO S.C.: Vice President Joe BidenJoe BidenPossible GOP challenger says Trump doesn't doesn't deserve reelection, but would vote for him over Democrat Joe Biden faces an uncertain path The Memo: Trump pushes back amid signs of economic slowdown MORE will headline a fundraiser for the South Carolina Democratic Party later this week, in a move likely to intensify speculation that he is preparing a run for the White House.

O’MALLEY BOTCHES AMA: Maryland Gov. Martin O’Malley (D) launched a Reddit "Ask Me Anything" thread on Monday and appeared to miss the point of the forum, answering even lighthearted questions from the notoriously tongue-in-cheek Redditors with humorless answers.