Republican presidential nominee Donald Trump gives a thumbs-up during an Oct. 13 rally in West Palm Beach, Fla. (Joe Raedle/Getty Images)

Less than three weeks before Election Day, the 2016 campaign is suddenly focused on an unusual, emotional and highly politicized topic for a presidential race: sexual assault.

Donald Trump and his surrogates have denied allegations that the candidate sexually assaulted nine women, casting doubts on their credibility, asserting their allegations are lies and, in Trump’s case, mocking their looks. At the same time, Trump and his allies have bolstered the stories of women who have accused Bill Clinton of sexual improprieties, castigating the media for not believing them.

Much of the debate has been shaped by cultural shifts in recent years that have dissipated the stigma of sexual assault and shifted public sympathy toward survivors, said Scott Berkowitz, president of the Rape, Abuse and Incest National Network (RAINN).

“It’s certainly become a much bigger part of the election than we ever anticipated,” Berkowitz said. “It’s a positive that the country’s talking about this issue and acknowledging it and that we’re not pretending it doesn’t exist, but certainly it’s disheartening at the same time.”

The debate has been particularly painful for many victims of sexual assault, who must endure nonstop coverage of allegations of groping and kissing without consent — along with backlash against the women who made the claims about Trump. Many also fear that brushing off allegations of sexual assault, as Trump and his backers have done, minimizes that it is a pervasive problem that affects millions of women and men.

In this video from 2005, Donald Trump prepares for an appearance on "Days of Our Lives" with actress Arianne Zucker. He is accompanied to the set by "Access Hollywood" host Billy Bush. The Post has edited this video for length. (Obtained by The Washington Post)

“Personally, it’s been really challenging to have our country talking about an issue that touches me so deeply and personally,” said Nikki Fortunato Bas, who attended a rally of sexual assault survivors at Trump Tower in New York on Tuesday. The events of the past few weeks have been a breaking point, she said, that led her to publicly say she had been assaulted.

She is not alone. In the wake of a 2005 tape in which Trump boasted that he could force himself on women because he was a “star,” author Kelly Oxford asked women to tweet stories of the first time they were assaulted — and more than 8 million people responded within 24 hours. Since the tape was first reported by The Washington Post on Oct. 7, RAINN said the number of people calling its hotline jumped by 35 percent.

Ebony Tucker, director of advocacy with the National Alliance to End Sexual Violence, said that such reactions are positive but that the debate has also come with negatives.

“A lot of the remarks that we’ve heard and a lot of the remarks that people have said brought to light a lot of the . . . archaic thinking people have around sexual assault,” she said during a Facebook Live event this week hosted by The Post.

Helen Brumley, a sexual assault survivor who appeared with Tucker, said Trump is “basically giving America a crash course on victim-blaming 101.”

In recent decades, politicians on both sides of the aisle have led fights to curb sexual assault and help victims. Sens. John Cornyn (R-Tex.) and Patrick J. Leahy (D-Vt.) have worked to help end a backlog of untested DNA from rape kits. The White House has fought sexual assault on college campuses, and administration officials, including Obama, will not travel to campuses that do not do a good enough job handling assault cases. Earlier this month, Obama signed a bill guaranteeing sexual assault victims certain rights under the law, including that they will not be charged for a sexual assault evidence kit.

Survivors and advocates share what it’s like to have sexual assault at the forefront of the presidential contest and a late night TV punchline, and discuss the benefits of sharing their stories. (TWP)

“Amidst the partisan bickering and gridlock in Congress, this law demonstrates that citizens can still effect positive change and that bipartisan progress is still possible,” Sen. Jeanne Shaheen (D-N.H.) said in a statement.

But in the 2016 presidential election, the issue has become sharply divided along partisan lines, including claims by some Trump allies that the behavior described by Trump’s accusers — groping and forced kissing — might not be considered assault.

Trump has also come under sharp criticism for suggesting last week that the women were not to be believed in part because they were not attractive enough for him to assault. In defending those remarks, Trump special counsel Michael Cohen said on CNN on Tuesday, “I think what Mr. Trump is really trying to say is that they’re not somebody that he would be attracted to and therefore the whole thing is nonsense.”

The resistance against the accusers is particularly awkward for the Trump campaign, which simultaneously argues that women who accused Bill Clinton of wrongdoing years ago should be believed. Before the second presidential debate, Trump campaign manager Kellyanne Conway retweeted an earlier message from Democratic nominee Hillary Clinton: “Every survivor of sexual assault deserves to be heard, believed, and supported,” adding: “ ‘Every’ being the operative word here.”

The Trump campaign did not respond to requests for comment this week on the issue.

Clinton has said that Trump “insulted and demeaned women,” along with other groups. She has pointed to others who have rebutted Trump’s remarks, including first lady Michelle Obama and professional athletes who struck back against Trump’s assertion that the comments on the tape were “locker room” talk.

At a rally in Ohio earlier this month, Clinton called Trump an “equal-opportunity insulter” and said his comments do not represent America.

That line of attack was expected to continue at Wednesday night’s debate.

“Hillary Clinton has directly confronted Donald Trump on the debate stage over his alarming and unacceptable comments, and she looks forward to having the opportunity to do so again,” Clinton spokesman Jesse Ferguson said.

Ashley O’Connor, a Republican strategist, said Trump has a core group of supporters who will stick with him no matter what.

“He’s clearly not backing down, attacking anybody who gets in his way, attacking women who are coming forward accusing him. It’s just incredible,” she said, noting that it is a tactic likely to turn off the swing voters and moderate women he desperately needs. “Part of winning a general election is winning that support, and I don’t see how that strategy does that.”

O’Connor said that Trump is in essence saying, “You need to believe the people who have come forward and accused Bill Clinton. You need to believe that Hillary Clinton was attacking these women. But don’t believe the women who have come forward against me.”

Katelyn Beaty, editor at large at Christianity Today, said that sexual assault has not been understood as an issue in the evangelical world and that churches have been slow to know what to do with the stories of women who are abused. Some of Trump’s evangelical supporters have claimed that Clinton was complicit in her husband’s behavior as a way to defend Trump.

“To me, that kind of response shows that evangelicals are coming at this from a political, ideological perspective rather than a matter of right and wrong or justice,” she said.

Beaty, for one, said she thinks that putting sexual assault into the political arena might not be a bad thing.

“I think, on one level, it should be politicized because questions of character and treatment of women should be aspects of what we look at in a presidential candidate,” she said.