If there’s one advantage that Hillary Clinton has over her fellow candidates in the 2016 election, it’s star power. The Democratic frontrunner has been racking up celebrity endorsements at a record pace: Kim Kardashian and Kanye West have snapped selfies with her, Beyonce has attended a fundraiser on her behalf, and everyone from Ariana Grande to Magic Johnson have tweeted their support of her candidacy.
But which of these boldface names are willing to go beyond social media and actually get out and stump for the former First Lady? Here’s a look at the celebrities who are pressing the flesh for her campaign:
Abby Wambach
The U.S. soccer star will be joining Clinton in New Hampshire this weekend. Wambach will be in Portsmouth for a Women for Hillary event before heading to a few other cities, including Dover, Concord and Keene. Last month, the presidential candidate posted a quote by Wambach on her Facebook page, with the caption “Congratulations on your retirement, Abby. Looking forward to cheering on U.S. Soccer with you at the Olympics this summer! #OnlyOneAbby”
Lena Dunham
Lena Dunham, the creator of HBO show Girls, is joining Wambach on the weekend’s New Hampshire tour. The vocal Clinton supporter debuted her weekly newsletter, Lenny Letter, with an interview with the former Secretary of State, and has jokingly alluded to Clinton’s ‘H’ logo as her “new tramp stamp” on Twitter.
Sign up: Click her to subscribe to the Broadsheet, Fortune’s daily newsletter on the world’s most powerful women.
Warren Buffett
The business mogul spoke at an Clinton campaign rally in Omaha last month, endorsing Clinton and saying that he backs her desire to tackle income inequality and raise taxes on the wealthy. Buffett, who rarely stumps for the candidates he supports, said that he believes Clinton “will make sure that those people who are having to work two jobs to barely get by will not have that kind of world for themselves and their children moving forward.”
Katy Perry
Pop star Katy Perry showed her support for Hillary by joining her on the campaign trail in Iowa last October, as well as taking over her Instagram during the state rally. After the rally, she posted an Instagram photo of her holding hands with Clinton, with a length caption explaining her support. “What I heard and experienced this weekend empowers me to believe that real change is possible and on the way,” she wrote.
Bill Clinton
Last but not least: Clinton’s husband—and former President—Bill Clinton, who has been stumping for his wife in New Hampshire this week, with plans to join her in Iowa on Thursday. Speaking to New Hampshire voters on Monday, he praised his wife’s record: “I do not believe in my lifetime anybody has run for this job at a moment of great importance who was better qualified by knowledge, experience and temperament to do what needs to be done now,” he said, according to the Associated Press.
Still, it remains to be seen whether Bill will be an asset or a liability to the Democratic frontrunner. Donald Trump has repeatedly slammed Clinton over her husband’s history of sexual transgressions and some women have questioned her decision to stand behind him despite his extramarital affair with White House intern Monica Lewinsky and a number of accusations of rape and sexual harassment. “You say that all rape victims should be believed. But would you say that about Juanita Broaddrick, Kathleen Willey, and/or Paula Jones?” asked one New Hampshire voter at a campaign event last month.
The competition
Clinton’s biggest Democratic competition, Vermont Senator Bernie Sanders, hasn’t been devoid of star power: comedian Sarah Silverman is a vocal supporter, and introduced him at a Los Angeles event back in August.
Unless you count Donald Trump’s reality TV bona fides, the Republicans appear to campaigning celeb-free—at least according to Fortune‘s scan of the field.
Does it matter?
Before writing off celebrity endorsements as window dressing, consider this: Oprah Winfrey’s endorsement of Obama over Hillary Clinton in the 2008 Democratic primary reportedly landed Obama over a million votes—more or less the same number by which he beat Clinton. Looks like that’s a lesson Clinton doesn’t plan to learn twice.