Democratic hopeful Hillary Clinton appears to be ahead of the game in the popularity contest, with dozens of pop stars, rappers and actors hopping aboard the #teamhillary bandwagon.
And she's not the only presidential hopeful to court, or be courted, by famous people...
Her rival Bernie Sanders is also notching up the stars, as is Republican frontrunner Donald Trump - a man better known for his celebrity status than his political acumen.
But their approach to endorsements, and how they are announced, seems to be continually evolving...
Hillary Clinton has won serious backing from the mainstream musical establishment, with a large number of pop stars and singers pinning their hopes on her becoming the first woman president of the United States of America.
Pop singers Katy Perry and Demi Lovato have both turned out to serenade the former first lady and performed at her many fundraisers. "She's my firework!" Perry told a crowd of supporters in Des Moines, Iowa, in October, dressed in a white strapless gown with Clinton campaign logo attached. Beyonce has also been spotted at a Clinton fundraiser in recent months.
Britney Spears appears to be undecided, after editing a post of her and Clinton meeting in Las Vegas this week to remove the #ImWithHer hashtag widely used by Clinton supporters.
Sir Elton John has confirmed he'll be headlining a New York fundraiser with Perry after Super Tuesday next month - but it won't be his first appearance, after he gave a musical performance to try to boost her dwindling campaign against Barack Obama in 2008, raising a mammoth $2.5m.
Bernie Sanders seems to be doing marginally better among the indie and punk crowd.
Last month, the Vermont senator joined indie rock group Vampire Weekend on stage at a rally ahead of the Iowa caucuses ,where he was seen bopping his head and singing along to Woody Guthrie's This Land Is Your Land. The song was reportedly covered by Sanders in a 1987 folk album.
Though Canadian, rock and roll musician Neil Young has also admitted to "Feeling the Bern" for Sanders. Red Hot Chili Peppers also hosted a fundraising concert in his honour this month.
It was widely reported in August that Clinton was seeking selfie advice from the "queen of selfies", Kim Kardashian. (It wouldn't be a celebrity story without mentioning the K-word.)
And her dream seemed to come true because a short while later Kardashian posted a selfie with Clinton on her Instagram account, in which they were photobombed by the one and only Kanye West.
"I really loved hearing her speak & hearing her goals for our country!" Kardashian wrote in her Instagram post.
West has announced his own plans to run for president in 2020, so perhaps he's hoping Hillary will put in a good word?
And it seems the whole Kardashian/Jenner family is getting behind Hillary. Kim's sister, Kendall, this week posted a selfie of herself posing in a Hillary Clinton t-shirt designed by Marc Jacobs.
Phil Robertson, the star of American reality TV series Duck Dynasty, is one of the few celebrities to endorse Texas Senator Ted Cruz.
And he did so by appearing in a paid-for video dressed in hunting gear duck hunting alongside the Republican presidential hopeful.
"Ted Cruz is my man, he fits the bill, he's Godly, he loves us, he's the man for the job and he will go duck hunting 'cos today we're going" - cut to image of Robertson and Cruz sat together in camouflage gear and faces covered in mud.
Cruz has even suggested Robertson would "make a great" UN ambassador - though it's not entirely clear if this was a joke or not.
And if you're from outside the US, you probably won't have even heard of Phil Robertson, or Duck Dynasty...
US actor Morgan Freeman, also known as Hollywood's "voice of God", has narrated a campaign ad for Hillary Clinton's presidential campaign.
"Her life's work has been about breaking barriers and so would her presidency," one of America's most recognisable voices booms out at the start of the 30-second campaign advert.
The Shawshank Redemption star, who has acted the role of president twice, joins a long list of celebrities to show support for the former secretary of state in her bid to get the Democratic nomination to run for the White House later this year.
The ad touts Clinton's early work fighting injustice in the southern states clearly trying to appeal to African-American voters.
Freeman also narrated an ad for President Obama's 2012 re-election campaign, which the New York Times reported was among the most effective to run from that cycle.
Rapper Killer Mike has given Bernie Sanders a tour of his hometown of Atlanta, accompanied the senator on the campaign trail and delivered impassioned speeches on his behalf in recent months. He also tweets prolifically about him.
The Run of the Jewels rapper first endorsed Sanders in June, saying he was backing the senator over his positions on healthcare, education and drugs policy.
More recently, Sanders has spoken in defence of Killer Mike after he came under fire for comments he made in which he quoted an activist who said: "A uterus doesn't qualify you to be president."
Sanders isn't the only candidate to rack up the rappers' vote. The legendary Snoop Dogg announced in May last year he would be voting for Hillary Clinton.
In January, a familiar face returned to the political scene in support of New York billionaire Donald Trump, the current Republican frontrunner.
Sarah Palin, the populist ex-Alaskan governor-turned-TV host, announced she was backing Mr Trump in the next presidential election.
"Are you ready to stump for Trump?" she asked a crowd of cheering supporters in Iowa.
She was John McCain's running mate in 2008 before they lost to Barack Obama, in a stint widely remembered for her gaffe-filled interviews.
It's not yet clear whether her support for Trump has had an impact on his campaign - since she was unveiled in January, her campaign appearances have been few.
And Donald Trump appears to have no shortage of celebrity endorsements.
One of the world's best known wrestlers, Hulk Hogan, said in August he wanted to be Mr Trump's running mate. Although he, too, appears to have gone quiet on that front.
More and more high-profile celebrities have been speaking out in support of who they think should become the next president of the United States.