(Bloomberg) -- JD Vance, the bestselling author of “Hillbilly Elegy,” joined the crowded Republican field in Ohio to replace retiring Senator Rob Portman in a key 2022 midterm race, saying the country needs “a new politics for a new generation.”

Vance, who grew up in poverty but went on to Yale Law School and a career as a venture capitalist, said he would be a “smart” fighter for causes such as breaking up big technology monopolies, raising taxes on companies that shift jobs overseas to the detriment of middle-class workers and opposing “woke” initiatives such as critical race theory.

“We have to send people to Washington who are willing to shake the system up, to fight, to fight smart and to make our country a little bit better,” Vance said at an announcement event on Thursday in his hometown of Middletown, Ohio, at the Middletown Tube Works that makes specialty welded steel tubing for the automotive and other industries.

Vance, 36, is a partner and co-founder of Narya Capital Management LLC and a Marine veteran. He rose to fame with the release of his best-selling memoir “Hillbilly Elegy” about growing up White and working-class in the Appalachia region of Ohio. Netflix adapted the book into a movie.

Vance enters the race with the advantage of backing from tech billionaire Peter Thiel, who donated $10 million earlier this year to a super political action committee supporting Vance’s run. The family of Robert Mercer, the former co-chief executive officer of Renaissance Technologies, also donated an undisclosed amount.

The GOP field already includes Josh Mandel, a former Ohio treasurer who ran unsuccessfully for the Senate in 2012 and in 2018 before withdrawing; Jane Timken, a former Ohio Republican Party chairwoman; Mike Gibbons, a businessman; Bernie Moreno, a car dealership owner and chairman of a blockchain technology company; Army veteran and emergency medical service pilot Michael Leipold; and Mark Pukita, founder of the information technology staffing firm Fast Switch Ltd.

The early part of the GOP race has been defined by Republican candidates trying to outdo each other in showing fealty to former President Donald Trump in hope of winning over his supporters and earn his endorsement in a state that voted for him twice by 8 percentage points.

Vance wasn’t always a Trump supporter, and his opponents have been bringing up comments he made in 2016 such as calling Trump “noxious” and saying his policy proposals “range from immoral to absurd.” Anonymous text messages have been circulating in Ohio calling Vance a “Never Trumper” and highlighting his past remarks criticizing Trump.

The Club For Growth political action committee, which has endorsed Mandel, issued a statement on Wednesday questioning Vance’s candidacy and saying, “Ohioans are asking, ‘Who’s the real JD Vance?”’

But Vance has said he came to support Trump based on his policies in office, especially his stance against China on trade. Vance has been active on social media and in media appearances touting pro-Trump and conservative positions, including opposing “woke capitalism.”

In a June 25 letter to Ohio Republican Party state central committee members, Vance acknowledged that he’s been critical of Trump but said he changed his mind “like many people did” and “took a lot of heat” for defending the former president and his supporters.

“People ask me what changed, and it’s pretty simple: at the time, I didn’t believe that a Democrat from New York would be able to accomplish much,” Vance said in the letter. “I was wrong, and importantly, the more I saw our ruling class from the inside, the more I realized he was right to attack them in the way he did.”

Representative Tim Ryan, who ran unsuccessfully for the Democratic presidential nomination in 2020, is the only declared Democratic candidate for the seat.

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