Republican Rep. Jim Renacci James (Jim) B. RenacciOhio is suddenly a 2020 battleground Democrats fear Ohio slipping further away in 2020 Medicare for All won't deliver what Democrats promise MORE (Ohio) announced Thursday that he’s running for Ohio’s Senate seat in 2018 after being encouraged by the White House to mount a Senate bid.

Renacci, who's been running in the Ohio governor’s race since last March, ended his gubernatorial bid and will instead run in the Republican primary to take on Sen. Sherrod Brown Sherrod Campbell BrownBipartisan praise pours in after Ginsburg's death Emboldened Democrats haggle over 2021 agenda Hillicon Valley: Russia 'amplifying' concerns around mail-in voting to undermine election | Facebook and Twitter take steps to limit Trump remarks on voting | Facebook to block political ads ahead of election MORE (D-Ohio).

His decision to jump into the Senate race comes days after Ohio state Treasurer Josh Mandel, who was considered the front-runner, surprisingly ended his bid, citing his wife’s health issues.

Renacci reportedly met with President Trump Donald John TrumpObama calls on Senate not to fill Ginsburg's vacancy until after election Planned Parenthood: 'The fate of our rights' depends on Ginsburg replacement Progressive group to spend M in ad campaign on Supreme Court vacancy MORE's political team this week, during which he was urged to run to unseat Brown.

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The 59-year-old Ohio congressman confirmed the decision during a Thursday morning appearance on AM 1420 The Answer in Cleveland.

"I now realize after meeting with the White House yesterday I really need to put country first and answer the call to action to serve our nation and come back to try and fight for the Trump agenda and try to get things done in the Senate," he said.

"When the president and the adminsitration calls you to action, it was a pretty compelling moment for me. So this morning I announce that, after speaking to my family and my advisers and my supporters, I've announced that I am going to switch and answer the call of the president, help the president in his quest to try to change Washington and I'm going to run against Sherrod Brown."

The Ohio representative has served in Congress since 2011 and has been a staunch supporter of Trump’s agenda over the last year. He is expected to play up his close relationship with the White House during the campaign. When the congressman announced his gubernatorial campaign, he launched a campaign website, OhioFirst.com, a nod to Trump’s “America First” slogan.

Renacci has pointed to a distaste for Washington as a central reason he decided to run for governor. When questioned about why he's trying to remain in Washington despite those concerns, Renacci pointed to his "belief in the president."

He recounted during the radio interview about how overtures from President Trump and his staff moved him from initial disinterest to ultimately deciding to run. Top White House aides invited him to a meeting to discuss a potential bid this week, where Renacci said the aides said he'd see an "overwhelming response from the president” if he jumped in.

"The message was delivered from all his senior advisers and the people on his staff that, ‘The president wants you to do this,'" he said.

Renacci's bid shakes up the top-tier race as other serious contenders weigh launching their own campaigns.

Renacci joins wealthy businessman Mike Gibbons, 64, who has been running for Senate since last May, in the GOP primary. Gibbons has been touting and rolling out more local endorsements, pledging to dump another $5 million into his campaign in the hopes of making other potential candidates second-guess a decision to jump in.

The GOP field could get another curveball as another high-profile contender mulls the race. J.D. Vance, 33, author of “Hillbilly Elegy,” is reportedly seriously considering a bid.

He initially ruled out a campaign last year, but has been reconsidering since Mandel’s exit. Donors have been encouraging him to run and Vance met with Republicans in Washington this week to discuss a potential bid. He also met with Senate Majority Leader Mitch McConnell Addison (Mitch) Mitchell McConnellObama calls on Senate not to fill Ginsburg's vacancy until after election Planned Parenthood: 'The fate of our rights' depends on Ginsburg replacement Progressive group to spend M in ad campaign on Supreme Court vacancy MORE (R-Ky.) on Monday.

The primary is on May 8, and the filing deadline for candidates is Feb. 7.

Whoever emerges from the Republican primary will have a tough battle against Brown, who has been in the Senate since 2007 and has been a staple in Ohio politics. He won his reelection in 2012 against Mandel by 6 points.

But Trump carried Ohio in the 2016 election by more than 8 points and the race is expected to draw national attention and millions of dollars as Democrats seek to protect incumbents in red states.

The Ohio Democratic Party responded with a statement painting Renacci, a member of the powerful House Ways and Means Committee, as a creature of Washington.

"Rep. Jim Renacci is the posterboy of Washington Republicans who’ve spent their time in office betraying middle-class workers to make life easier on the wealthy and well-connected," Ohio Democratic Party spokesman Jake Strassberger said in the statement.

"He brings nothing to the table but a record of giving away tax breaks to multi-millionaires like himself, while making Ohio families pay more for their healthcare and empowering corporations to send good Ohio jobs overseas.”

Renacci took a similar swipe at Brown on the radio, making it clear the two will seek to use their possible opponent's Washington experience as a bludgeon.

"Sherrod Brown is the epitome of a career politician. Sherrod Brown is everything I've said is wrong with Washington," Renacci said, arguing that Brown is also too liberal to represent Ohio.

The GOP congressman starts with a fundraising disadvantage. While he's been raising money for his gubernatorial bid, he cannot transfer that money over to his Senate bid. After putting his federal fundraising on pause for his gubernatorial bid, he has just $286,000 in his campaign account as of Sept. 30.

Renacci told AM 1420 that he's already raised and spent a lot on his gubernatorial bid, including a chunk of his personal wealth, and said he'd do "whatever is necessary."

By comparison, Brown, 65, has amassed an enormous war chest as he prepares for reelection. His campaign announced that he closed the year with $9.8 million banked away, twice what he had on hand at this point in the 2012 cycle.

Updated at 11:22 A.M. EST.