In a letter sent Monday to supporters, Cooper announced that he will instead seek re-election as the state's top law enforcement official.

"Many of you have encouraged me to pursue leadership roles in North Carolina's future, and I'm honored with the trust you place in me," Cooper said in the letter.

However, Cooper told supporters that he loves his current job and the impact he has on people's lives and wants to continue his work as attorney general. He added, "I get up every morning excited about helping make North Carolina a better and safer place to be."

Cooper was unavailable for comment.

Cooper's decision narrows the field of candidates known to be considering seeking the Democratic nomination to Lt. Gov. Beverly Perdue, state Treasurer Richard Moore, and Rep. Bill Faison of Orange County. Both Perdue and Moore have already raised at least $1 million, while Cooper had raised about $750,000, according to campaign finance reports.

It was unclear Tuesday, based on campaign finance records, how much Faison may have raised.

Gov. Mike Easley, a Democrat, cannot seek a third consecutive term under the state constitution.

Among Republicans, U.S. Rep. Sue Myrick backed out of running for governor in May, leaving two active candidates: Salisbury lawyer Bill Graham, who spent $1 million of his own money to oppose a state gas tax hike, and state Sen. Fred Smith, a Clayton businessman.

However, several other Republicans have been mentioned as potential candidates, including former state Sen. Patrick Ballantine, the 2004 GOP nominee for governor; Jim Cain, the U.S. ambassador to Denmark; and state Sen. Robert Pittenger of Charlotte.