WASHINGTON — Alabama Republican Roy Moore says a lawsuit will be filed over the newspaper report carrying allegations that he had sexual contact with a 14-year-old girl four decades ago and that neither Democrats nor Republicans want to see him win a special Senate election.

While pressure to quit the race four weeks before Election Day intensified from within the Republican Party, Moore assured supporters Sunday night at a Huntsville, Alabama, gym that the Washington Post story was "fake news" and "a desperate attempt to stop my political campaign."

Moore said allegations that he was involved with a minor child are "untrue" and said the newspaper "will be sued," drawing a round of applause. The former judge also questioned why such allegations would be leveled for the first time so close to the special election in spite of his decades in public life.

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"Why would they come now? Because there are groups that don't want me in the United States Senate," he said, naming the Democratic Party and the Republican establishment and accusing them of working together. He added, "We do not plan to let anybody deter us from this race."

The Post story quoted four women by name, including the woman who alleged the sexual contact at 14, and had two dozen other sources.

Moore also tried to raise money from the controversy, writing in a fundraising pitch sent about midafternoon that the "vicious and sleazy attacks against me are growing more vicious by the minute." He told supporters, "I'm counting on you to stand with me at this critical moment by chipping in a donation to help me bust through the vicious lies and attacks and get the truth out to as many voters as possible before December 12."

Another fellow Republican, Sen. Pat Toomey of Pennsylvania, urged Moore to drop out of the race. He said Moore's explanations had been inadequate and that Republicans should consider Sen. Luther Strange as a write-in candidate to run against Moore. Strange lost the Republican primary to Moore in September.

Even if Moore were to step aside, his name would likely remain on the ballot. And any effort to add Strange as a write-in candidate would threaten to divide the GOP vote in a way that would give the Democratic candidate a greater chance of winning.

Toomey did not rule out the possibility that Senate Republicans might work to unseat Moore if he wins the special election against Democrat Doug Jones.

"You know, this is a terrible situation, nearly 40-year-old allegation, we'll probably never know for sure exactly what happened," Toomey said on "Meet the Press" on NBC. "But from my point of view, I think the accusations have more credibility than the denial. I think it would be best if Roy would just step aside."

The White House, pointedly noting that President Donald Trump did not back Moore during the primary, said Trump will likely weigh in on the Senate race when he returns from Asia later this week. The White House has already made clear that Moore should step aside if the allegations are proven to be true.

"I think there's a special place in hell for those who actually perpetrate these crimes," White House legislative aide Marc Short said Sunday.

"But, having said that, he hasn't been proved guilty," Short added. "We have to afford him the chance to defend himself."

Moore is an outspoken Christian conservative and former state Supreme Court judge. The Post reported last Thursday that he had sexual contact with a 14-year-old girl and pursued three other teenagers decades earlier.

While he called the allegations "completely false and misleading," in an interview with conservative radio host Sean Hannity he did not wholly rule out dating teenage girls when he was in his early 30s. Asked if that would have been usual for him, Moore said, "Not generally, no."

The story stirred concern among anxious GOP officials in Washington in a key race to fill the Senate seat once held by Jeff Sessions, now the U.S. attorney general. Losing the special election to a Democrat would imperil Republicans' already slim 52-48 majority in the Senate, which is hoping to pass a tax overhaul later this year. But a Moore victory also would pose risks if he were to join the Senate GOP with a cloud of sexual misconduct allegations.

In the immediate aftermath of the Post report, a wave of national Republican leaders called for Moore to drop out of the race if the allegations are true. They included the head of the House Freedom Caucus, Rep. Mark Meadows of North Carolina, Senate Majority Leader Mitch McConnell of Kentucky and Texas Sen. Ted Cruz.

Over the weekend, more Republicans distanced themselves from Moore, including Sens. Bob Corker of Tennessee and Tim Scott of South Carolina.

Toomey and Short appeared on NBC's "Meet the Press," Scott spoke on CBS' "Face the Nation."