WASHINGTON – President Donald Trump’s refusal to concede the 2020 election to President-elect Joe Biden continued into Sunday, with Democrats urging respect for the vote’s integrity and the president’s staunchest allies defending his unfounded claims of fraud and blitz of lawsuits.

But more cracks appeared in what has largely been a wall of silence from senior GOP figures on the president’s still-incendiary rhetoric contesting the vote. Former President George W. Bush offered Biden his congratulations, and a few moderate Republicans pressed the case for “cooler heads” to prevail.

And adding to a long list of heads of state and government offering congratulations to Biden, Saudi Arabia’s de facto leader, Crown Prince Mohammed bin Salman, did so Sunday, as did Israeli Prime Minister Benjamin Netanyahu. Trump’s relations with the powerful crown prince and with Netanyahu are among his friendliest personal ties in the ranks of global leaders.

On Sunday, as was the case throughout a bitter campaign, the president and president-elect presented a study in contrasts: Trump unleashed a series of grievance-laden tweets before heading for his Virginia golf property, while Biden attended church, then turned with his team to transition business.

The COVID-19 pandemic, meanwhile, presented an ever-grimmer backdrop to the political tumult, with the two narratives continuing to intertwine. One of the nation’s leading public health experts, former Food and Drug Administration commissioner Scott Gottlieb, warned that the little over two months between now and Inauguration Day, Jan. 20, might be among the outbreak’s bleakest weeks.

“The reality is that by the time the president-elect takes office, we’ll probably be at sort of the apex, if you will, of what we’re going through right now,” he said on CBS’ “Face the Nation.” Gott- lieb added that the usual hoopla surrounding a U.S. president’s swearing-in would need to be curtailed.

“I don’t think we’re going to be able to bring large crowds together for an inauguration,” he said. “We’re going to be right in the thick of probably the worst point of this epidemic.”

Biden, who on Monday plans to name a coronavirus working group for his administration, has repeatedly vowed to heed scientists’ advice on how best to stem the spread of the virus. Nearly 240,000 Americans have died from it and almost 10 million have been infected.

As Trump continued to resist accepting the outcome of the vote, called Saturday by most major news organizations, some leading Democrats, and a few Republicans, saw genuine peril in his ongoing campaign to undermine public confidence in the electoral system. The House majority whip, Rep. James Clyburn, declared on CNN’s “State of the Union” that “this democracy is teetering.”

Clyburn, D-S.C., said he wasn’t as much concerned with the question of whether or when Trump concedes, because the victor will take office either way, but “whether or not the Republican Party will step up and help us preserve the integrity of this democracy.”

Maryland Gov. Larry Hogan, a Republican who has voiced disagreement with Trump over issues including his handling of the pandemic, said it may take “a few more days for cooler heads to prevail” on a concession of defeat by the president.

“Whether you like it or not, it’s time to get behind the winner” of the 2020 race, Hogan said on “State of the Union,” adding that he had not seen evidence of any malfeasance or error in vote counting that would change the results.

Utah Sen. Mitt Romney, a Republican who has often crossed the president, said Trump was staying true to type. “I would prefer to see a more graceful departure, but that’s just not in the nature of the man,” he said, also on CNN.

In a separate interview on NBC’s “Meet the Press,” Romney called Trump “the 900-pound gorilla when it comes to the Republican Party,” suggesting that he did not expect his own views to be widely echoed within the GOP until Trump comes around to the idea of having lost.

Trump’s most hard-line allies gave no ground in the face of widespread commentary from experts that his legal challenges were highly unlikely to yield any game-changing rulings.

On Fox’s “Sunday Morning Futures,” a parade of prominent congressional Republicans including Sen. Ted Cruz, Rep. Kevin McCarthy and Sen. Lindsey Graham, the chairman of the Senate Judiciary Committee, insisted that the president was right to fight on.

“At this point, we do not know who has prevailed in the election,” asserted Texas’ Cruz.

“Every legal challenge should be heard, then, and only then, that America will decide who won the race,” said McCarthy (R-Bakersfield), the House minority leader.

“President Trump should not concede,” said South Carolina’s Graham.

Election law expert David Becker, however, doubted the various claims would hold up under legal scrutiny.

“What we’re seeing now is crazy allegations being thrown around on Twitter and elsewhere,” he said on CBS. “And when it goes to court, they fall apart. There’s nothing there.”

Trump himself appeared to be behind the unyielding Republican stance, said senior Biden campaign adviser Symone Sanders.

“I think the White House has made clear what their strategy is here, and that they are going to continue to participate and push forward these flailing and, in many respects, baseless legal strategies,” she said on “State of the Union.”

Sanders said the Biden camp had heard nothing from the White House, but that some GOP members of Congress were beginning to reach out. Biden campaign co-chair Rep. Cedric Richmond, D-La., predicted that the former vice president would draw on his decades in the Senate to reach out across the partisan divide, particularly on coronavirus relief.

“I think Vice President Biden will be a different kind of president. I think he’s going to be able to bring House members from the Republican side, House members, Senate Republicans together on legislation,” Richmond said on CBS. “He served with many of them.”

In what could mark the start of a quiet thaw, the only living Republican former president on Sunday broke his silence on the election to congratulate Biden and his running mate, Sen. Kamala Harris of California, the first woman of color to ascend to the vice presidency.

“Though we have political differences, I know Joe Biden to be a good man, who has won his opportunity to lead and unify our country,” Bush, the 43rd president, said in a statement. He said he offered Biden the same thing he had to Trump and to former President Barack Obama at the start of their terms: prayers and a pledge to help in any way he could.

Los Angeles staff writer Sarah D. Wire contributed to this report from Washington.