Katy Perry at Inauguration 2013 (Pictures)

It's no secret President Obama has a lot of celebrities on his side, and for his inauguration festivities, supporters like Kerry Washington, Eva Longoria, and Allison Williams hit the party scene in Washington DC to celebrate the momentous event. At the Commander in Chief's Ball, Alicia Keys turned out an amazing performance — singing a remix of "Girl on Fire" as "Obama's on Fire" — and rocked a beaded red dress from Michael Kors. Not long after, Jennifer Hudson serenaded the first couple with her rendition of Al Green's "Let's Stay Together" in a body-hugging black halter gown and glitter-soled platform pumps. Between the balls, the soirees, and one star-studded hip-hop party, there are enough enviable looks to go around. Check the slideshow to see which celebrities stepped out (stylishly) to celebrate Obama's big day now!