Breaking with President Trump’s drive to overturn his election loss, Senator Mitch McConnell of Kentucky on Tuesday congratulated President-elect Joseph R. Biden Jr. on his victory and began a campaign to keep fellow Republicans from joining a last-ditch effort to reverse the outcome when Congress tallies the results next month.
Although Mr. McConnell’s moves came weeks after Mr. Biden was declared the winner, they amounted to clear effort by the majority leader, who is the most powerful Republican in Congress, to put an end to his party’s attempts to sow doubt about the election. They were also a bid to avoid a messy partisan spectacle on the floor of the House that could divide Republicans at the start of the new Congress, pitting those loyal to Mr. Trump against institutionalists.
“Many of us hoped that the presidential election would yield a different result, but our system of government has processes to determine who will be sworn in on Jan. 20,” Mr. McConnell said in a speech on the Senate floor. “The Electoral College has spoken. So today, I want to congratulate President-elect Joe Biden.”
A short time later, on a private call with Senate Republicans, Mr. McConnell and his top deputies pleaded with their colleagues not to join members of the House in objecting to the election results on Jan. 6, when Congress meets to ratify the Electoral College’s decision, according to three people familiar with the remarks.
A small group of House members, led by Representative Mo Brooks of Alabama, plan to use a constitutional process to object to the inclusion of five key battleground states that day. There is almost no chance they would succeed, but if they could convince at least one senator to join them, they could turn the counting session into a chaotic last stand for Mr. Trump.
So far, no senator has committed to joining them. And though Mr. McConnell could not stop one of them from doing so if they wished, he made clear that the challenge would be futile and embarrassing for the Senate.
His public remarks were a decisive shift for Mr. McConnell and came hours after members of his leadership team, and even the Senate chaplain, began softening the ground by congratulating Mr. Biden Monday evening and Tuesday morning.
The incoming president and the majority leader, who served alongside one another in the Senate for decades, spoke by phone short time later, apparently for the first time since the election.
“I called to thank him for the congratulations, told him although we disagree on a lot of things, there’s things we can work together on,” Mr. Biden said, adding that it was a “good conversation.”
Vice President-elect Kamala Harris echoed Mr. Biden’s comments in an ABC interview on Tuesday.
“I applaud Mitch McConnell for talking to Joe Biden today,” she said. “It would have been better if it were earlier, but it happened, and that’s what most important, and so let’s move forward.”
Though he never repeated them, Mr. McConnell had allowed Mr. Trump’s baseless allegations of widespread voting fraud or fantastical claims that he had won the election by a wide margin to circulate unchecked for more than a month. Allies insisted privately that he would ultimately honor the election results but did not want to stoke a year-end conflict with the president that could hurt the party’s chances in…