Some of Donald Trump's most fervent and loudest supporters on the MAGA right are pointing to Wednesday's Senate GOP leadership election as the first major test of Republican loyalty to the president-elect, and the final battle between Trump and his occasional Republican nemesis, outgoing GOP leader Mitch McConnell.

       Republican senators meet behind closed doors on Wednesday morning to cast their votes to choose McConnell's successor in a three-person race that pits two senators -- John Thune and John Cornyn -- who are seen as McConnell proteges and the third -- Rick Scott -- who has pledged his loyalty to Trump.

       Former President and Republican presidential candidate Donald Trump attends a town hall meeting in Cumming, Georgia, Oct. 15, 2024.

       Elijah Nouvelage/AFP via Getty Images

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       Many of Trump's most high-profile supporters -- including Elon Musk, Steve Bannon and Tucker Carlson -- are loudly campaigning against Thune and Cornyn, saying the race will determine whether the Republican-controlled Senate will be sufficiently loyal to the Trump agenda.

       As Carlson put it, "Rick Scott of Florida is the only candidate who agrees with Donald Trump. Call your senator and demand a public endorsement of Rick Scott."

       Sen. Rick Scott speaks during Day 2 of the Republican National Convention in Milwaukee, Wisconsin, July 16, 2024.

       Mike Segar/Reuters

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       Those campaigning against Thune and Cornyn portray the race as more than a leadership battle.

       "We're taking over every institution of government," one prominent Trump ally told me. "This is not a transition. You do understand that, right? We're taking over and it starts with the Senate."

       But for all the blunt talk about the Senate race, Trump has not taken sides and all indications are that he won't. One key factor, sources close to the president-elect say, is that Trump doesn't think Rick Scott can win the race and the last thing he wants to do is endorse a loser.

       Even without that endorsement, Scott is running as the one real pro-Trump candidate in the race, saying under his leadership the Senate agenda will be "identical to the Trump agenda."

       Senate Minority Whip John Thune speaks to reporters next to U.S. Senate Minority Leader Mitch McConnell following the weekly Senate caucus luncheons on Capitol Hill in Washington, Sept. 24, 2024.

       Piroschka Van De Wouw/Reuters

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       Thune and Cornyn both endorsed Trump and say they are also committed to passing the Trump agenda.

       But both have also shown a willingness to occasionally stand up to Trump. After he voted to acquit Trump in the Senate impeachment trial in February 2021, for example, Thune said: "My vote to acquit should not be viewed as exoneration for his conduct on January 6 … or in the days and weeks leading up to it. What former President Trump did to undermine faith in our election system and disrupt the peaceful transfer of power is inexcusable."

       Cornyn has said Trump used "reckless and incendiary speech" on Jan. 6. and criticized Trump's handling of COVID-19.

       Sen. John Cornyn questions a witness during a Senate Intelligence Committee hearing on Capitol Hill in Washington, Mar. 8, 2023.

       Mary F. Calvert/Reuters

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       While Trump himself has not endorsed any candidate, over the weekend he made two big demands of all three of them: 1) He wants them to promise confirm cabinet secretaries without a vote in the Senate if necessary (through the use of so-called "recess appointments"); and, 2) He wants them to block confirmations of any judges while the Democrats still control the Senate.

       Scott responded almost immediately, announcing on X he would go along with Trump's demands: "100% agree. I will do whatever it takes to get your nominations through as quickly as possible."

       In a sign of Trump's influence, Thune and Cornyn also expressed support for Trump's demand, both saying they are committed to doing everything possible to quickly confirm Trump's nominations and saying they are open to recess appointments, too.

       But if either Thune or Cornyn emerges as the next Republican leader in the Senate, it may be a sign that Trump’s influence is not unlimited – or, at that very least, that a Republican leader can show some independence and still survive in Trump’s Republican Party.