Senate Majority Leader Mitch McConnell, R-Ky., is expected to rebuke the GOP challenge to certify the Electoral College results for President-elect Joe Biden on Wednesday, sources tell Fox News. If so, it would be his first public statement against President Trump's supporters in Congress on the matter. 

TRUMP SLAMS MCCONNELL, CORNYN, THUNE AS 'WEAK AND INEFFECTIVE' RINOS AHEAD OF ELECTORAL CERTIFICATION

A coalition of more than a dozen GOP lawmakers in both the House and Senate are gearing up for a fight during Congress' joint session, a battle they are likely to lose but that has caused a stir for opponents unhappy with the challenge to the results of the presidential election. The effort by some Republicans is a last-ditch show of unwavering loyalty to President Trump, who has lobbed numerous unsubstantiated claims and filed several lawsuits in battleground states blaming widespread voter fraud for his November loss. 

Meanwhile, a source familiar with Wednesday's vote told Fox News McConnell plans to be one of the first speakers to object to initial challenges by colleagues in his own party, driving home the importance of certifying the votes -- which have been approved by all 50 states -- and ensuring a peaceful transfer of power. 

In private, McConnell has warned Republicans -- many of whom will be up for reelection in 2022 -- the grave political ramifications of attempting to stymie Biden's transition into the White House but has publicly shied away from going toe-to-toe with the president. 

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Trump has kept up a steady barrage of tweets, praising Sens. Ted Cruz, Ron Johnson and others, who have pledged to vote against certifying the election results, while simultaneously lambasting McConnell and any other Republican who refuse to stand with them. 

"I hope the Democrats, and even more importantly, the weak and ineffective RINO section of the Republican Party, are looking at the thousands of people pouring into D.C. They won't stand for a landslide election victory to be stolen. @senatemajldr @JohnCornyn @SenJohnThune," Trump said on Twitter Tuesday, stoking supporters who flocked outside the White House overnight to protest Congress' vote. 

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Freshman Sen. Josh Hawley, R-Mo., has said he will challenge Pennsylvania's electoral votes and Sen. Kelly Loeffler, R-Ga., has said she may challenge the votes in her state as well. Cruz, leading a group of 11 senators who want to create a commission to examine groundless allegations of election fraud, is expected to challenge Arizona's votes.