Hamm, Bialik, Questlove join White House campaign against sexual violence

The White House has enlisted Hollywood stars including Jon Hamm of "Mad Men" and Connie Britton of "Nashville" to help fight campus sexual assault.

President Barack Obama and Vice President Joe Biden are unveiling the "It's On Us" campaign Friday at a White House event.

A website that went live Friday morning, ItsOnUs.org, features a public service announcement with Obama, Biden and other familiar faces telling viewers it's their responsibility to stop sexual assault. The star power also includes NBA all-star Kevin Love, actresses Kerry Washington, Rose Byrne and Mayim Bialik, comedian Joel McHale and musicians Randy Jackson and Questlove.

With an estimated one in five college women attacked, the campaign encourages everyone on campus to make sure friends are safe and to intervene before an assault happens. The message is particularly targeted at men, with the White House pointing to research that shows that men are often reluctant to speak out against violence against women because they believe other men accept it.

"It's on us to stop sexual assault," Hamm says in a close-up shot that opens the video.

"To get in the way before it happens," Washington continues.

Others chime in to encourage viewers to make sure friends get home safe and not to blame the victim or look the other way. Obama closes the video by referring to the pledge and the website.

The campaign is being supported by partners who plan to help spread the message, including the NCAA, several collegiate athletic conferences and media companies with reach among students. The NCAA plans to promote anti-assault messages on screens at their championship events. Video game maker Electronic Arts will encourage fans to sign up to pledge to support the campaign through its online platforms. And media giant Viacom will promote the messages on websites, including for music channels MTV, VH1, BET and CMT.

Visitors to the website are asked to turn their social media profile pictures into the shape of the campaign logo. They are asked to use their name, email address and zip code to pledge "not to be a bystander to the problem, but to be a part of the solution." The information is collected by Generation Progress, the youth arm of the liberal Center for American Progress advocacy organization with close ties to the White House.

The event comes as students are settling in for a new year on campus and follows other White House efforts that have been helping raise awareness about the problem that typically remained in the shadows. Research has shown most victims know their attackers, alcohol or drugs are often involved and only 12 percent of college women attacked report it to police.

Obama decried the statistics as "totally unacceptable" in a January speech and launched the White House Task Force to Prevent Students from Sexual Assault. The task force recommended actions campuses could take to protect victims, such as identifying confidential victim's advocates and conducting surveys to better gauge the frequency of sexual assault on their campuses. And the U.S. Department of Education for the first time publicly exposed the list of colleges under federal investigation for their handling of sexual assault complaints.