Washington, D.C. ? Saying “I made a mistake,” Republican Sen. Judd Gregg of New Hampshire abruptly withdrew as commerce secretary nominee Thursday and left the fledgling White House suddenly coping with Barack Obama’s third Cabinet withdrawal.

Gregg cited “irresolvable conflicts” with Obama’s policies, specifically mentioning the $790 billion economic stimulus bill and 2010 census in a statement released without warning by his Senate office.

Later, at a news conference, he sounded more contrite.

“The president asked me to do it,” he said of the job offer. “I said yes. That was my mistake.”