DES MOINES, Iowa &045; Sen. Barack Obama, bidding to become the nation’s first black president, captured the Iowa caucuses Thursday night, opening test in the race for the 2008 Democratic nomination. Mike Huckabee rode a wave of support from evangelical Christians to victory in the Republican caucuses.

Obama, 46 and a first-term senator from Illinois, eased past a high-powered field that included Sen. Hillary Rodham Clinton of New York, the former first lady, and former Sen. John Edwards of North Carolina, the party’s 2004 vice presidential nominee.

Among Republicans, Huckabee, a preacher turned politician, handily defeated Mitt Romney despite being outspent by tens of millions of dollars, and deciding in the campaign’s final days to scrap television commercials that would have assailed the former Massachusetts governor.

Obama, who campaigned as an apostle of change in Washington, was gaining 36 percent support among Democrats., Edwards, who ran promising to battle the special interests in the capital, and Clinton, who stressed her experience, both were drawing about 30 percent.

Huckabee’s triumph was more robust. He was winning 34 percent support, compared to 25 percent for Romney. Former Sen. Fred Thompson and Sen. John McCain battled for third place.