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.

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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

🎂Happy Birthday🎂 to our next great leader @hillaryclinton !!! This past weekend, I was honored to be able to sit down with Maya Harris, one of HRC’s senior policy (aka plans for the future) advisors before joining the stage with Hillary the next day. I wanted to be more informed and educated on her plans and dreams for our country. I never want to be a puppet, and always want to feel my own purpose and ownership in everything I do. Maya and I, and some of my closest girlfriends, had the most incredible, eye-opening 3 hours of conversation about the future. We went over so many points and asked the hard questions on everything from gun control to birth control to health care to affordable education to a realistic approach in finding the middle class again. I was never raised with economic privilege and found money to be the main source of pain for my own family growing up, so I understand why there is a need for such change. I am still learning and educating myself on the world of politics and searching for every strand of authenticity buried deep in it. What I heard and experienced this weekend empowers me to believe that real change is possible and on the way! Ladies! There are so many incredible opportunities for us that are possible: equal pay, paid leave (you don’t lose your job if you want to have a family) and YOUR choice to have a family when and if it’s RIGHT FOR YOU! These are just some of the reasons I am standing with her and will continue to do so. Next year’s election is one of the most important ones in decades, and the choices we make will have a profound effect on women for years to come. So, I stand with her for my daughters and their daughters, and beyond what time gives me. Get informed, get involved and become empowered! Strong women help create strong families! ❤️ See link in bio for 📷 from the weekend👗 by @bcompleted

A photo posted by KATY PERRY (@katyperry) on Oct 26, 2015 at 5:44pm PDT

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.