South Carolina Republican Rep. Russell Fry announced Monday he's running for the U.S. Senate seat held by the late Lindsey Graham, entering what is shaping up to be a crowded GOP primary as Republicans vie to continue Graham's conservative legacy.

"South Carolina, I'm in! I'm running for the U.S. Senate," Fry wrote on X. "We need a conservative fighter in the Senate who delivers real results. I will be your conservative MAGA candidate in the special primary Senate election this summer."

Fry pledged to tackle high gas prices and rising grocery costs while aligning himself closely with President Donald Trump's America First agenda.

The announcement comes just days after Trump endorsed interim Sen. Darline Graham Nordone, Graham's sister, if she decides to seek the full term.

Politico reported that Fry's candidacy sets up the possibility of a high-profile Republican primary between two candidates with close ties to the president.

"There is no other way to put it: Lindsey Graham was one of a kind. There is no replacing him," Fry said in a statement, Politico reported. "But I believe the best way to honor his legacy is to fight alongside the President just as steadfastly as he did."

Fry emerged as a leading contender almost immediately after Graham's unexpected death.

Trump backed Fry in 2022 when he defeated then-Rep. Tom Rice, who had voted to impeach Trump after Jan. 6, 2021. Since arriving in Congress, Fry has become a reliable Trump ally.

The president last week told Newsmax that Fry would be an "outstanding" choice for the Senate seat.

"I think Russell Fry, a young congressman, is outstanding, and I could see that happening," Trump said on "Greg Kelly Reports." "He's a very, very talented person."

Still, the race remains fluid.

Semafor reported Friday that Darline Graham Nordone has indicated to the White House she is considering a full Senate campaign after Trump promised her his "complete and total endorsement" if she runs.

Her candidacy could spare House Republicans from losing another member in their razor-thin majority while giving GOP voters another Trump-backed option.

Other Republicans considering bids include Reps. Nancy Mace, Ralph Norman, Lt. Gov. Pamela Evette, businessman Mark Lynch, and former Gov. and Rep. Mark Sanford.

An Emerson College Polling/Nexstar survey released last week underscored the race's uncertainty.

No candidate reached 20% support, with Norman leading at 16.4%, followed by Lynch at 12.5%.

Fry drew 9.4%, while Nordone received 5.9%, and nearly 18% of Republican voters remained undecided.

South Carolina Republicans will choose their nominee in a special primary Aug. 11, with a runoff scheduled for Aug. 25 if no candidate wins a majority.

The GOP nominee will face Democrat Annie Andrews in November to complete the remainder of Graham's term.