Updated 11:51 p.m. | Republican Sen. Jeff Flakejoined calls from Democrats on Sunday to hit pause on Brett Kavanaugh’s Supreme Court nomination to get more information from a woman who went public with details of an alleged sexual attack by Kavanaugh decades ago when they were both in high school.

The comments by the Arizona lawmaker, a member of the Senate Judiciary Committee, are the first sign of trouble for Majority Leader Mitch McConnell’s push for a confirmation vote on Kavanaugh this month.

Christine Blasey Ford, a California college professor, told The Washington Post that when she was 15 years old, and Kavanaugh was around 17 and a junior in high school in Bethesda, Md., he pinned her to a bed at a party, groped her over her clothes and attempted to pull off her one-piece bathing suit and the clothing she wore over it. When she tried to scream, she said, he put his hand over her mouth, The Post reported.

“For me, we can’t vote until we hear more,” Flake told The Post hours after Ford’s interview was published. Republicans hold an 11-10 advantage on the committee, so every GOP vote is crucial to moving forward the confirmation process.

The committee could still vote on Kavanaugh’s confirmation, but if Flake joined Democrats in opposing President Donald Trump’s pick then the nomination could be reported unfavorably to the Senate floor.

Judiciary Chairman Charles E. Grassley is working to set up calls for Republican and Democratic committee staff with Kavanaugh and Ford ahead of Thursday’s scheduled vote, a panel spokesman said.

Democrats called Sunday for a delay in Thursday vote until there is an investigation.

Sen. Dianne Feinstein, the committee’s top Democrat who got a letter from Ford in June, said in a news release that she supports Ford’s decision to share her story. “And now that she has, it is in the hands of the FBI to conduct an investigation,” Feinstein said. “This should happen before the Senate moves forward on this nominee.”

Her fellow Californian, Sen. Kamala Harris, was among the other Democratic committee members calling for a delay, for what she dubbed a “credible and serious allegation.”

“The Senate has a constitutional responsibility to scrutinize SCOTUS nominees,” Harris said on Twitter. “A vote on Kavanaugh’s nomination must be delayed until there is a thorough investigation.”

Senate Minority Leader Charles E. Schumer of New York also called for a delay until there is an investigation. “For too long, when women have made serious allegations of abuse, they have been ignored. That cannot happen in this case,” Schumer said in a news release.

“Judge Kavanaugh’s credibility has already been seriously questioned because of his answers regarding Manny Miranda, Judge Pryor, and other issues during his time in the Bush White House, and now his credibility is even more suspect,” Schumer said. “To railroad a vote now would be an insult to the women of America and the integrity of the Supreme Court.”

But a statement from a committee spokesman cast doubt that Grassley and other Republicans believe the details given by Ford in her interview warrant a delay in the committee.

“It’s disturbing that these uncorroborated allegations from more than 35 years ago, during high school, would surface on the eve of a committee vote after Democrats sat on them since July,” Taylor Foy wrote in a news release on behalf of Judiciary Republican. “If Ranking Member Feinstein and other Committee Democrats took this claim seriously, they should have brought it to the full Committee’s attention much earlier.”

Foy called on Feinstein to publicly release the letter from Ford. “It raises a lot of questions about Democrats’ tactics and motives to bring this to the rest of the committee’s attention only now rather than during these many steps along the way,” he wrote.

South Carolina Sen. Lindsey Graham agreed with the concerns of the committee and has been a consistent voice in support of Kavanaugh, but he was the first Judiciary Republican to take a different approach.

“If Ms. Ford wishes to provide information to the committee, I would gladly listen to what she has to say and compare that against all other information we have received about Judge Kavanaugh,” Graham said in a news release. “If the committee is to hear from Ms. Ford it should be done immediately so the process can continue as scheduled.”

Kavanaugh does not plan to withdraw and maintains his denial issued Friday, when the allegation first became public but with fewer details, a White House official said. Kavanaugh “categorically and unequivocally” denied the allegation, as he said in Friday’s statement.

Watch: Judiciary Democrats Object to Kavanaugh Vote Plan, But Date is Set