WASHINGTON — The White House weighed in on sexual misconduct allegations swirling about GOP Senate candidate Roy Moore during the president's Asia trip Friday.

White House spokeswoman Sarah Huckabee Sanders told reporters aboard Air Force One en route to Vietnam that “like most Americans the president believes we cannot allow a mere allegation, in this case one from many years ago, to destroy a person’s life. However, the president also believes that if these allegations are true, Judge Moore will do the right thing and step aside.”

On Thursday, Senate Republicans were quick to distance themselves from Moore, saying he should drop out of the Alabama special election if sexual misconduct allegations against him are true.

"If these allegations are true, he must step aside," said Majority Leader Mitch McConnell of Kentucky, establishing a line that was repeated by an array of his Senate Republican colleagues.

In a Washington Post story published Thursday, a woman said Moore engaged in sexual touching with her when she was a teenager and he was in his 30s in the late 1970s. Three other women told the Post Moore pursued romantic relationships with them when they were teens in the same time period.

Moore, a controversial former state Supreme Court chief justice, is running against Democrat Doug Jones, a former U.S. attorney, in a Dec. 12 special election for the seat ex-senator Jeff Sessions gave up to become President Trump's attorney general.

Moore vehemently denied the charges, calling it "fake news.'' His campaign called the allegations "completely false."

"This garbage is the very definition of fake news and intentional defamation,” campaign chairman Bill Armistead said in a statement.

Moore blamed the story on Democrats, tweeting: "The Obama-Clinton Machine’s liberal media lapdogs just launched the most vicious and nasty round of attacks against me I’ve EVER faced! We are are in the midst of a spiritual battle with those who want to silence our message."

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With Democratic election victories in statehouse races in Virginia and New Jersey on Tuesday, attention has focused on the competitive race in Alabama.

Republicans are counting on a win in the red state, where President Trump beat Democrat Hillary Clinton by a 2-1 margin in 2016. Republicans hold a slim 52-48 majority in the Senate and cannot afford to lose an otherwise safe seat.

Polls have shown Moore holding a narrow lead over Jones.

Moore beat Sen. Luther Strange, who was appointed to fill the seat after Sessions's departure, in a Republican primary in September, even though Trump supported Strange.

Moore, a polarizing figure even in his own party, was in Washington last week, where he spoke briefly to Republican senators at their weekly policy lunch in the U.S. Capitol.

He has publicly railed against Republican leaders, including McConnell, who endorsed Strange in the Republican primary.

Moore became a national figure in 2003 when he was removed as chief justice of the Alabama Supreme Court for refusing to follow a federal court order to take down a Ten Commandments monument from a judicial building.

He was later re-elected and then suspended in 2016 for ordering the state’s probate judges to not issue marriage licenses to same-sex couples even after the state same-sex marriage ban had been overturned.

Several senators, including Richard Shelby, the senior Republican senator from Alabama, said last week they supported Moore's bid.

But the tone changed Thursday afternoon.

“If these allegations are true, there is no place for Roy Moore in the United States Senate,” Shelby said in a statement.

Alaska Republican Sen. Lisa Murkowski said Strange should launch a write-in campaign if the allegations are true.

Strange didn't respond to questions from reporters Thursday. His office also did not respond to several calls and emails.

South Dakota Sen. John Thune, a GOP leader, told reporters Republicans are looking into steps to replace Moore if the allegations are true.

“The allegations against Alabama Senate candidate Roy Moore are deeply troubling,” Colorado Sen. Cory Gardner, chairman of the National Republican Senatorial Committee, said in a statement. “If these allegations are found to be true, Roy Moore must drop out of the Alabama special Senate election.''

Some Alabama officials dismissed the allegations.

"Even if you accept the Washington Post’s report as being completely true, it’s much ado about very little," Alabama State Auditor Jim Zeigler told the Montgomery Advertiser.

Moore will remain on the ballot no matter what happens over the next few weeks.

Alabama Secretary of State John Merrill said Thursday ballots have already been printed. Moore has given no indication of withdrawing from the race, but if he did and still drew the most votes, a second special election would have to be called.

Sen. John McCain, R-Ariz., who was reserved in his support of Moore last week, called the allegations “deeply disturbing and disqualifying.’’

“He should immediately step aside and allow the people of Alabama to elect a candidate they can be proud of,” he said in a statement Thursday.

The Senate Leadership Fund Political Action Committee — which is aligned with McConnell — spent millions to back Strange in the primary. It shifted its support to Moore after the primary, but hedged again Thursday.

"If there’s even a shred of evidence to these accusations, Gov. Ivey and the Alabama Republican Party need to do everything in their power to remove Judge Moore from the ballot,'' Steven Law, president and CEO of the Senate Leadership Fund, said in a statement. "There is no place in our party for sexual predators."

Contributing: Brian Lyman, Eliza Collins, Deirdre Shesgreen and David Jackson