With the 2012 Presidential vote just 11 days away, Katy Perry is voicing her support for Barack Obama's campaign for re-election.

Performing Oct. 24 at the America Forward! Grassroots event in Las Vegas, the "Part of Me" singer proved her point through fashion -- donning a skintight white dress with the phrase "President of the United States" that proudly displayed a ballot with the Obama-Biden box checked. His opposition Mitt Romney's box was left empty.

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Perry, 28, accessorized her look with red heels and an American flag jewel-encrusted microphone. (At Obama's "30 Days to Victory" fundraiser in L.A. earlier this month, she showed off a patriotic, Obama-themed manicure featuring the Commander-in-Chief's face on her fingers.)

During the event, the singer encouraged those in attendance to make their vote count on Nov. 6. "Don't wait. Go tomorrow. How many of you are 18 here? It's going to be your first time, right?" Perry said.

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President Obama was clearly pleased with Perry's participation in his Wednesday fundraiser. "I've [gotten] to know Katy and she's a wonderful young lady. And I can tell that part of it is because of her outstanding grandma, a 50-year resident of Nevada," Obama, 51, told the crowd.

"The only thing I have to say is she got some lipstick on me when she kissed me. Fortunately somebody wiped it off before Michelle saw it," he continued. "I'm telling you, you're going to get me in trouble!"

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Perry, who celebrates her 28th birthday on Thursday, took to Twitter after the event to gush over her meeting with Obama. "So tonight was a great night!" she wrote. "The PRESIDENT gave grandma and I unforgettable shout outs & now I am officially 28! Best. birthday. ever."

This article originally appeared on Usmagazine.com: PICTURE: Katy Perry Wears Presidential Ballot Dress, Supports Obama in Las Vegas