The singer – who is engaged to Nashville-based talent manager Brandon Blackstock – attended the inaugural ball with her fiancé on Monday.
Sharing her political partying experience with her 2.6 million followers, Clarkson, 30, chronicled her evening on Twitter.
"My dress barely fit in the car for tonight's festivities. I feel like Cinderella! Thank you Oscar De La Renta!" she Tweeted, revealing a photo of herself wearing a floral patterned gown.
Then it was time to pose for photos with Blackstock. "Me and Brandon in our 'fancy' attire :) Fun night!" she later Tweeted.
Though Clarkson assured followers she was having a ball, she credited the First Lady with getting the festivities going.
"Just partied at the White House ....I kid you not, Michelle Obama stood up and got the party started ....seriously cool First Lady :)," she Tweeted.