U.S. Sen. Johnny Isakson was re-elected to a second term Tuesday, defeating state Labor Commissioner Mike Thurmond to cap a campaign that was dominated by the popular GOP incumbent.

At around 10 p.m., Isakson claimed victory. As he took the podium to address supporters, Isakson picked up his granddaughter, Elizabeth, and said his victory was about a commitment he made to her.

"I will not be one of the first generations of American public servants to leave my children and grandchildren worse off than my parents left me," Isakson said.

Thurmond conceded shortly before 11 p.m., leaving a voicemail message of congratulations for Isakson and offering the senator his support.

Thurmond told The Associated Press he was "disappointed, but delighted that I had the opportunity to serve as the Democratic nominee and just blessed to have been the Georgia Labor Commissioner for the past 12 years."

"It was a great run," he said.

During the campaign, the 65-year-old Isakson branded himself a conservative in opposition to the Democratic administration in Washington and vowed to cut taxes, control federal spending and repeal health care legislation backed by President Barack Obama.

Early in the campaign, Isakson's health was raised as an issue after he was hospitalized for an infection, but he dismissed the concerns and kept an active campaign schedule.

Isakson, a retired real estate executive and former state representative and congressman, raised nearly $9 million and dominated the airwaves with a series of football ads designed to show his willingness to fight the liberal agenda in Washington.

Thurmond, a popular Democrat serving his third term as labor commissioner, surprised the state's political observers when he announced he would not seek re-election in favor of challenging Isakson.

The 57-year-old Athens native touted his experience and record of job creation, but struggled to raise money. The latest filing showed he had raised about $270,000.

Donovan, a 53-year-old veteran airline pilot, questioned Isakson's conservative credentials and vowed to make cutting federal spending a top priority. Donovan had raised about $16,000 during the campaign.

Tags: Georgia, Washington, conservative, Labor Commissioner Michael Thurmond, U.S. Senator Johnny Isakson, elections, GOP, victory, Democratic administration