WASHINGTON – President Barack Obama was sworn in for four more years Sunday in a simple ceremony at the White House, embarking on a second-term quest to restore a still shaky economy and combat terrorists overseas while swearing an age-old oath to “preserve, protect and defend” the Constitution.

“I did it,” a smiling president said to his daughter Sasha seconds after following Chief Justice John Roberts in reciting the oath of office. First lady Michelle Obama and the couple’s other daughter, Malia, were among relatives who bore witness.

The quiet moments were prelude to today’s public inaugural events when Obama and Vice President Joe Biden will be sworn in on the steps of the U.S. Capitol before a crowd expected to reach into the hundreds of thousands and a TV audience counted in the millions.