Clarkson, however, once said she was a fan of Republican presidential candidate Ron Paul for the 2012 race, although she said she voted Obama in 2008.
She said on Twitter on Wednesday she is "excited & honored" to be performing at the inaugural.
Richard Blanco, 44, is also set to be the youngest ever inaugural poet and the first Hispanic or gay to recite a poem at the ceremonial swearing-in.
"His contributions to the fields of poetry and the arts have already paved a path forward for future generations of writers," Obama said in a statement. "Richard's writing will be wonderfully fitting for an inaugural that will celebrate the strength of the American people and our nation's great diversity."
Obama also gave a nod to the diversity of styles and backgrounds of the musical performers, saying that "their music is often at the heart of the American story and speaks to folks across the country".
The official celebration will include the swearing-in on the Capitol's west front, followed by a luncheon inside the building's Statuary Hall for 200 including congressional leaders, Cabinet members and Supreme Court justices.
Planners said the lunch menu will feature steamed lobster, New England chowder, hickory grilled bison with wild huckleberry reduction and red potato horseradish cake and a dessert of apple pie, ice cream, cheese and honey.
- AP
