JoJo
The "Too Little Too Late" singer teams up with DoSomething.org for the "Lose Your V-Card" campaign that celebrates the importance of registering to vote
Leonardo DiCarpio & Al Gore
The actor snaps a picture with the politician. "Ran into this #climatechange pioneer at the@unitednations this morning," he Instagrammed.
Jay-Z, Beyonce & Barack Obama
Hip-hop royal couple meet the president of the United States after Jay-Z and Beyoncé hosted a $40,000-ticket fundraiser for the Obama campaign at the rapper's 40/40 Club.
Shakira
This do-gooding pop star joins forces with President Obama to speak out about early childhood development at the 6th Annual Summit of the Americas in Colombia.
Scarlett Johansson
She fights crime in The Avengers—and, in real life, for political causes she believes in! Black Widow's alter ego attends a campaign fundraiser for Manhattan Borough President Scott Stringer in New York City.
Hayden Panettiere
Guess who's a hero to the citizens of Washington, D.C.? Mayor Vicent Gray honors the actress-activist for her work on behalf of D.C. self-determination and statehood.
Paul McCartney & Barack Obama
The President presents the erstwhile Beatle with the prestigious Gershwin Prize for Popular Song, awarded by the Library of Congress, honoring the musician's career spent helping "lay the soundtrack for an entire generation."
Garth Brooks & Barack Obama
The president bestows the country legend with a special "Grammy on the Hill" Award honoring his work on behalf of recording arts. Talk about friends In high places!
George Clooney & Joe Biden
The former ER doc met with the vice president in February to discuss his latest trip to Chad and the border of Darfur.
Beyoncé & Jay-Z
The power couple, along with millions of their closest friends, witness the inauguration in the nation's capital.
See all the celebs who descended upon Washington in our Inaugurating Obama gallery!
Oprah Winfrey & Jesse Jackson
At an election rally in Chicago's Grant Park Tuesday night, the talk-show queen and the reverend are all smiles upon hearing the news that Barack Obama just won the presidency.
Brad Pitt
In between shooting a new movie and diaper duty, the actor manages to find time to join the thousands gathered in Chicago to hear Obama address the crowd after winning the election.
Paris Hilton
The socialite casts her ballot and strikes a pose at an L.A. polling station.
Lindsay Lohan
The actress spends some time with a fellow voter after taking part in the election process at a residential garage in West Hollywood, Calif.
Ben Affleck
He voted. Did you? (Judging from the amazing turnout, yes indeed, you voted.)
Harvey Weinstein & Jessica Alba
The mogul and the marvelous new mama are among the revelers at a bipartisan party at Public House in New York City.
Kim Kardashian
An added bonus of voting? You might run into somebody who looks like this.
Peter Sarsgaard & Maggie Gyllenhaal
The talented couple come out to vote together in the Park Slope neighborhood of Brooklyn.
Pete Wentz
The Fall Out Boy frontman proudly points to his "I Voted" sticker outside an L.A. polling station. Back in August the emo darling and his band headlined the Rock the Vote Ballot Bash in Denver during the Democratic National Convention.
Sarah Jessica Parker, Matthew Broderick & James Wilkie
Between the SATC star manning the phones on behalf of the Obama campaign and her actor hubby utilizing Ferris Bueller-isms to try and get people to the polls, it's no surprise that we not only spotted the two casting their ballots bright and early in the Big Apple Tuesday but that they shared the experience with their 6-year-old son as well.
Sean Combs
Diddy did his thing inside a polling booth at a New York City high school, and thanks to a number of video blogs by the man himself, it's certainly no secret which candidate received his vote.
Cynthia Nixon
On Election Day, the actress naturally discusses politics with fellow voters in North Miami Beach, Fla., in particular Amendment 8, which would allow counties in the area to propose a sales tax increase to help raise funds on behalf of community colleges.
Ben Affleck
The outspoken actor has never hidden his leftist leanings, which made his recent imitation of equally partisan MSNBC host Keith Olbermann on Saturday Night Live all the more enjoyable to watch. And while not exactly flattering, we're hoping the former ESPN newsman was a good, well, sport about it.
Bruce Springsteen
The Boss gave added meaning to rock the vote when he joined Barack Obama and family at a Cleveland campaign stop during the last weekend before the big election. In addition to performing in front of about 80,000 supporters, the music icon also shared his views on why he believes Obama was born to run. The country, that is.