West Virginia Gov. Jim Justice (R) has formally filed paperwork with the FEC to challenge Democratic Sen. Joe Manchin in 2024, raising the chances that Republicans can retake the Senate.

Why it matters: This could be the toughest potential race of Manchin's career, if Justice survives an expected primary challenger and further media scrutiny.

• Justice officially announced his bid Thursday, criticizing the Biden administration's policies on energy, inflation and immigration, saying, "We're gonna have to do something about it and we're gonna have to elect somebody that has done it."
• "I'm hung up on the truth. I am hung up on being a patriot," he added.
• Justice's approval rating in West Virginia is at 64%, vs. 40% for Manchin, as Axios' Josh Kraushaar previously reported.
• The governor first faces a primary against Rep. Alex Mooney (R-W.V.), a member of the Freedom Caucus.
• "Make no mistake, I will win any race I enter," Manchin said in statement after the news of Justice's filing broke.

Zoom in: Justice, a coal mining and agribusiness magnate, assumed office in 2017 as a Democrat. But months later, he revealed he was switching his party affiliation to Republican at a rally with then-President Trump.

• Since then, voters in the state have re-elected Justice, and his recent work has focused on popular conservative causes.
• In 2022, he signed an abortion ban that only allows exceptions for medical emergencies, rape, or incest.
• The governor then helped shepherd through what he called the largest tax cut in West Virginia's history, slashing income taxes in part to help attract new residents.
• He also signed legislation this year allowing concealed carry on public college campuses.

What they're saying: South Carolina Sen. Lindsey Graham introduced Justice during the rally Thursday, saying, "We need help in Washington. We need a winner. ... A conservative who can move the ball forward."

Between the lines: Justice entering a national race is bound to draw renewed scrutiny to his businesses and personal finances.

Editor's note: This article has been updated with additional details throughout.