U.S. president Obama marks 48th bithday

Obama will have lunch with Senate Democrats at the White House, White House press secretary Robert Gibbs said Monday. They are likely to discuss health care, the economy, energy legislation and the "Cash for Clunkers" program.

Obama kicked off his birthday a few days early with a weekend trip to Camp David. Along with his wife, daughters and mother-in-law, he was joined Saturday by longtime Chicago pals Marty Nesbitt, chairman of the Chicago Housing Authority Board, and physician Eric Whitaker, along with several of the president's childhood friends from Hawaii, according to an administration official.

At his Maryland getaway, the president played basketball and bowled. Obama, who was chided during the campaign for his unimpressive bowling skills, bowled a 144 over the weekend, Gibbs said -- a marked improvement from the 37 and gutter balls Obama rolled as a presidential candidate in March 2008 in Altoona, Pa, The Washington Post reported.