Supreme Court nominee, Brett Kavanaugh, takes notes as the Senate Judiciary Committee members make opening statements during his confirmation hearing, on Capitol Hill in Washington, Tuesday, Sept. 4, 2018.

J. Scott Applewhite/AP

Colorado U.S. Sen. Cory Gardner’s office has confirmed it received a letter Monday accusing U.S. Supreme Court nominee Brett Kavanaugh of inappropriate behavior against a woman two decades ago. The message was anonymous and contained no contact information, but a staff member did say it did have a Denver postmark.

Kavanaugh already faces accusations by three other named women, including one from Colorado.

The letter relates a 1998 incident in which the writer claims that during a night out in Washington, D.C., her daughter witnessed Kavanaugh shove a woman he was dating. Gardner’s office turned the letter over to the Senate Judiciary Committee. Kavanaugh was asked about it during a call with committee members Wednesday, as first reported by NBC. Kavanaugh dismissed the accusation, saying "It's ridiculous. Total twilight zone."

"On September 24th our Denver office received an anonymous letter in the mail about an alleged incident with Brett Kavanaugh in 1998," Gardner's office said in a statement. "The letter contained no names, no address, and no contact info. Upon receiving the anonymous letter we immediately notified the Senate Judiciary Committee, which is handling the confirmation of Judge Kavanaugh.  The letter was shared with both Republican staff and Democrat staff."

The statement continued, "Due to privacy regarding mail that comes into our office, we do not share the content of correspondence. Additionally, this anonymous letter contained no name or no contact info so our office is unable to contact the individual that sent the anonymous letter."

The Judiciary Committee released the email, which reads (including original grammar and punctuation): 

“Dear Cory Gardner,

I will remain anonymous but I feel obligated to inform you of this 1998 incident involving Brett Kavanaugh.

When he was author of the Star Report, my daughter (from Boulder Colorado) occasionally socialized with Brett Kavanaugh. She and a group of four (including  Kavanaugh met in a Washington D.C. bar).

Her friend was dating him, and they left the bar under the influence of alcohol. They were all shocked when Brett Kavanaugh shoved her friend up against the wall very aggressively and sexually.

There were at least four witnesses, including my daughter.

Her friend, still traumatized, called my daughter yesterday, September 21, 2018, wondering what to do about it.

They decided to remain anonymous.”

Earlier Wednesday, NPR reported that the committee is reviewing a statement from a third woman,  identified as Julie Swetnick, who has come forward with sexual misconduct allegations against Kavanaugh.

The allegations from Swetnick were made public by attorney Michael Avenatti on Wednesday morning.

Avenatti posted Swetnick's three-page sworn declaration on Twitter.

Meanwhile, the lawyer for Deborah Ramirez of Colorado, who says Kavanaugh exposed himself to her at a party when they attended Yale University, raised her profile in a round of television interviews, AP reported.

The Senate Judiciary Committee will hear from just two witnesses Thursday: Kavanaugh and Christine Blasey Ford, a California psychology professor who accuses him of attempting to rape her when they were teens.

Attorneys for Ramirez are arguing with Republicans on the Senate Judiciary Committee over how to address her allegations.

“We had a phone call scheduled [with] them last night that the majority party blew off,” Ramirez lawyer John Clune told NPR’s Morning Edition. “So, unless we can have a meaningful conversation with them and they’re actually going extend the offer it for her to testify then it’s really a moot point.”

Republicans for the committee led by Sen. Chuck Grassley of Iowa said they have repeatedly sought evidence from Ramirez to back up her claims and none was provided.

NPR reported that Trump signaled Wednesday there's a lot riding on Kavanaugh's planned testimony Thursday and, for the first time, acknowledged he could withdraw the high court nomination if he decides that Ford is telling the truth about an alleged incident from the 1980s.

"[Democrats] are actually con artists, because they know how quality this man is and they've destroyed a man's reputation, and they want to destroy it even more." Trump told journalists in New York.

"And they know it's a big, fat con job," he continued. "And they go in to a room, and I guarantee you, they laugh like hell on what they pulled off on you and on the public, they laugh like hell. "

Trump said the allegations of the three women "are all false to me," bemoaning "what they've done to these children — these beautiful children of (Kavanaugh's), and what they've done to his wife."