Eva posted a picture of herself cheering with her arms aloft as she heard Obama would return for a second term as president.
"We did it!!! Obama re-elected!!!!! Yes!! Yes We Can! Barack Obama re-elected as 44th President of the USA!!!! Go @BarackObama," she wrote.
"Me and my friends celebrating! I'm on tears! Moving the country forward!!! Obama!!! (sic)."
Many other stars used the social networking site to back Obama. Among them was Olivia Wilde, who could barely contain her excitement.
"AMERICA! You have spoken! Women! You have been heard! Young people! You proved them wrong! Tireless Obama volunteers! I THANK YOU! (sic)," she wrote.
"Thank God #Obama2012 has victoriously won I feel Safer now there hopefully wont be a world war III & gays can finally get married! #victory (sic()," she wrote.
Jay-Z and Beyoncé Knowles have been open about their admiration for the president, helping raise fund for his campaign.
Beyoncé chose last night to join Instagram, posting a picture of herself in a T-shirt emblazoned with the phrase 'Texans for Obama' on the photograph sharing website.
Lady Gaga could barely contain herself after hearing Obama had been re-elected.
"I JUST GOT OFF STAGE IN COLUMBIA!! CONGRATULATIONS MR. PRESIDENT," she wrote. "We are so proud to be American tonight! YES!!! YES! YES!! We just couldn't be happier my goodness, the joy when freedom prevails (sic)."