WASHINGTON >> A new accuser said today that as a teenager in the 1970s she was sexually assaulted by Roy Moore in a locked car, further rocking the Alabama Republican’s race for an open Senate seat. The allegation came on day when Senate Majority Leader Mitch McConnell said Moore should quit the contest, and Moore fired back that it was McConnell who should step down.

Even before the news conference by Beverly Young Nelson, Moore’s campaign released a statement saying that attorney Gloria Allred — who’s representing Nelson — “is a sensationalist leading a witch hunt.” It said Moore is innocent and “has never had any sexual misconduct with anyone.”

In tears, Nelson said in New York that when she was 16, Moore offered her a ride home from the restaurant where she worked. She accused him of touching her breasts and locking the door to keep her inside his car. She said he squeezed her neck while trying to push her head toward his crotch and tried to pull her shirt off.

Moore finally stopped and as she fell or was pushed out of the car, he warned her no one would believe because he was a county district attorney, Nelson said.

Before Monday, Moore was already battling allegations reported last week by The Washington Post that he had sexual contact with a 14-year-old girl decades ago when he was in his 30s and pursued romantic relationships with three other teenagers.

“I believe the women,” McConnell, R-Ky., said Monday in response to a question at an appearance in Louisville, Kentucky. He said flatly that Moore should step aside for another GOP candidate.

When the Post’s story first broke last Thursday, McConnell had said Moore should step aside if the allegations were true.

McConnell said a write-in effort by another candidate was a possibility.

“That’s an option we’re looking at — whether or not there is someone who can mount a write-in campaign successfully,” McConnell said. Asked specifically about current Sen. Luther Strange, the loser to Moore in a party primary, he said, “We’ll see.”

Shortly after McConnell made his remarks Monday, Moore tweeted his response.

“The person who should step aside is SenateMajLdr Mitch McConnell. He has failed conservatives and must be replaced. #DrainTheSwamp,” Moore wrote.

The crossfire escalated a GOP civil war over Moore’s Senate candidacy in a Dec. 12 special election, which until last week’s allegations was viewed as an inevitable Republican win in the deep-red state.

On the Democratic side, one of the Senate’s moderate members is helping Moore’s challenger raise campaign funds, underscoring the party’s wary approach in an Alabama race that until recently was viewed as a virtually certain win for the GOP.

In fact, the fundraising bid by Sen. Joe Donnelly, D-Ind., doesn’t mention allegations about Moore.

“Doug’s opponent, Roy Moore, is an extremist with a record of putting political ideology above the rule of law,” Donnelly wrote in a weekend email soliciting contributions for Democrat Doug Jones. Moore and Jones face a Dec. 12 special election to replace Strange, who was appointed to replace Jeff Sessions when Sessions was named U.S. attorney general.

In a further indication of Democrats’ caution, the party’s No. 2 Senate leader, Richard Durbin, dodged a question Sunday about what the Senate should do if Moore is elected. He tried to shift the focus back to Republicans.

“President Trump is the leader of the Republican Party in America. It’s his responsibility to step forward and say more and do more when it comes to the situation in Alabama,” Durbin, D-Ill., said on CNN’s “State of the Union.”

Moore said a lawsuit will be filed over the Post report that detailed the allegations against him.

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 article 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.

“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.”

Moore, too, has tried to raise money from the controversy, writing in a fundraising pitch that the “vicious and sleazy attacks against me are growing more vicious by the minute.”

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.

Moore is an outspoken Christian conservative and former state Supreme Court judge.

The situation has stirred concern among anxious GOP officials in Washington in a key race to fill the Senate seat once held by Sessions. Losing the special election to a Democrat would imperil Republicans’ already slim 52-48 majority. But a Moore victory also would pose risks if he were to join the Senate GOP under a cloud of sexual misconduct allegations.