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"As the new Congress was sworn in Sunday, the Republican Party splintered badly as at least 12 senators planned to join about 140 House members to contest Joe Biden's election win," Politico reports. "The tensions are so high that individual GOP senators are now directly battling" in "open warfare against each other." While Senate Majority Leader Mitch McConnell (R-Ky.) is asking his caucus to accept President Trump's loss, House Minority Leader Kevin McCarthy (R-Calif.) is reportedly giving his GOP colleagues the green light to object to the Electoral College results on Wednesday.

McCarthy's predecessor, former House Speaker Paul Ryan (R-Wis.), urged Republicans to knock it off in a rare public statement Sunday. "Efforts to reject the votes of the Electoral College and sow doubt about Joe Biden's victory strike at the foundation of our republic," Ryan said. "It is difficult to conceive of a more anti-democratic and anti-conservative act," and "the fact that this effort will fail does not mean it will not do significant damage to American democracy." Trump has "had ample opportunity to challenge election results, and those efforts failed from lack of evidence," he added. "Joe Biden's victory is entirely legitimate."

Also on Sunday evening, all 10 living former defense secretaries signed an op-ed in The Washington Post affirming Biden's victory and warning that the military should not be dragged into Trump's effort to contest his loss. The signatories include James Mattis and Mark Esper, who served under Trump, as well as conservative stalwarts like Donald Rumsfeld and Dick Cheney. Cheney, who was also vice president for eight years, came up with the idea for the joint statement, said William Perry, former President Bill Clinton's defense secretary.

"American elections and the peaceful transfers of power that result are hallmarks of our democracy," the defense secretaries said. "Our elections have occurred. Recounts and audits have been conducted. Appropriate challenges have been addressed by the courts. Governors have certified the results. And the electoral college has voted. The time for questioning the results has passed; the time for the formal counting of the Electoral College votes, as prescribed in the Constitution and statute, has arrived."

Chuck Hagel, a Republican who served as defense secretary under President Barack Obama, told the Post he considered whether warning about military intervention was an overreaction, but decided it was better to nip the idea, raised by some close Trump allies, in the bud.