President Obama helped ring in the Christmas season in Washington tonight at a celebrity-filled concert hosted by Ellen DeGeneres at the National Building Museum. In between being serenaded by pop stars like Mariah Carey, Annie Lennox, and Maxwell, Obama gave a speech in which he touched on the Christian origins of the holiday and gave a shout-out to the troops. “We pray for our troops. We remember those who are out of work and struggling to get by,” he said, urging the crowd to participate in charity. The concert was also attended by first lady Michelle, their two daughters, and Michelle’s mother Marian Robinson. The concert will air Friday night on TNT.