Updated at 11:23 a.m. ET

Following yet another legal setback for the Trump campaign, Republican Sen. Pat Toomey of Pennsylvania called on President Trump to accept the outcome of the Nov. 3 election and move forward with the transition process in order to protect his presidential legacy.

"President Trump has exhausted all plausible legal options to challenge the result of the presidential race in Pennsylvania," Toomey said in a lengthy statement.

His Saturday night statement came soon after a federal judge dismissed a Trump campaign lawsuit challenging the results in Pennsylvania by alleging that election officials in Democratic-leaning counties allowed voters to fix errors on their mail-in ballots. The Trump campaign has vowed to the appeal the ruling.

President-elect Joe Biden won the state by more than 80,000 votes. The state's deadline to certify those results is Monday.

Toomey — who is retiring rather than running for reelection in two years — added his congratulations to Biden and Vice President-elect Kamala Harris, saying he will "seek to work across the aisle" with them despite their policy disagreements.

"Make no mistake about it, I am deeply disappointed that President Trump and Vice President Pence were not re-elected. I endorsed the president and voted for him," he said, applauding the Trump administration for its tax policy and three appointments to the Supreme Court.

But, he added: "To ensure that he is remembered for these outstanding accomplishments, and to help unify our country, President Trump should accept the outcome of the election and facilitate the presidential transition process."

For his part, Trump tweeted his disapproval of Toomey, calling him "no friend of mine." The tweet was flagged by Twitter for its baseless claims about election fraud.

What other Republicans have said

While most Republican Senate and House lawmakers have not yet formally recognized Biden as the winner of the presidential election, Sens. Susan Collins of Maine, Ben Sasse of Nebraska, Mitt Romney of Utah and Lisa Murkowski of Alaska have all issued statements recognizing Biden's victory.

Romney recently issued a blistering rebuke of Trump after the president invited Republicans in Michigan's House and Senate to the White House, days ahead of the deadline for that state to certify its election results.

"It is difficult to imagine a worse, more undemocratic action by a sitting American President," Romney tweeted.

But those senators are in the minority.

Lamar Alexander of Tennessee, another Republican senator who won't seek another term, said in a statement Friday: "If there is any chance whatsoever that Joe Biden will be the next president, and it looks like he has a very good chance, the Trump Administration should provide the Biden team with all transition materials, resources, and meetings necessary to ensure a smooth transition so that both sides are ready on day one."

Sen. Kevin Cramer, R-N.D., told NBC's Meet the Presson Sunday that he believes the president's continued legal quest is appropriate.

"I don't see this as an attack on our democracy," he said. "Everyone ought to just relax and let it play out in the legal way. We'll be just fine."

However, he said it is "past time" for the White House to cooperate in the transition process with the Biden team.

"I'd rather have a president that has more than one day to prepare, should Joe Biden end up winning this," Cramer said.

But the third-ranking House Republican, Rep. Liz Cheney of Wyoming, has called on Trump to respect the "sanctity of our electoral process."

"If the President cannot prove these claims or demonstrate that they would change the election result, he should fulfill his oath to preserve, protect and defend the Constitution of the United States," she said in a statement Friday.

Former New Jersey Gov. Chris Christie, a Republican, called the conduct of Trump's legal team a "national embarrassment," speaking Sunday on ABC's This Week.

"I've been a supporter of the president's. I voted for him twice. But elections have consequences, and we cannot continue to act as if something happened here that didn't happen," Christie, an ally of Trump, said.

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