DES MOINES, Iowa (Reuters) - Barack Obama took the first step to winning the Democratic presidential nomination on Thursday with a victory in Iowa, while Mike Huckabee capped a stunning political rise to beat Republican rival Mitt Romney.
Obama, an Illinois senator bidding to make U.S. history as the first black president, won the first Democratic test on the road to the White House with a win over New York Sen. Hillary Clinton and former North Carolina Sen. John Edwards, who were in a tight battle for second.
Huckabee, a former Arkansas governor and ordained Baptist minister, was projected by television networks to beat Romney fairly easily despite being dramatically outspent by the wealthy former Massachusetts governor and venture capitalist.
For the winner in Iowa, the prize is valuable momentum and at least a temporary claim to the front-runner's slot in their battle to win the party's presidential nomination in the November election.
The third-place finisher in the heavyweight Democratic showdown, meanwhile, could find themselves hobbling into New Hampshire for Tuesday's primary.
The 2008 campaign is the most open presidential race in more than 50 years, with no sitting president or vice president seeking their party's nomination.
The loss was a heavy blow for Clinton, the former first lady who a few months ago was considered in some quarters the almost certain Democratic nominee. The loss creates immense pressure to turn around her campaign in New Hampshire over the next five days.
Obama's win effectively makes him the candidate to beat among Democrats, and a win next week in New Hampshire could set him on a nearly unstoppable drive to the nomination. The next big contest would be in South Carolina, where more than half of the voters are black.
Iowa voters filled gathering spots in more than 1,700 precincts around the state to declare a presidential preference in Iowa's caucuses, which open the state-by-state battle to choose candidates in the November 4 election to succeed President George W. Bush.
In the Democratic caucuses, voters debated their options and cajoled their neighbors to switch to their candidate. Republicans conducted essentially a preference poll, casting votes soon after the caucus begins.
For Republicans, Huckabee's upset reshaped a race where no candidate has been able to claim front-runner status.
Iowa, where a sizable bloc of religious conservatives had fueled Huckabee's rapid rise, represented perhaps the best chance for the former Arkansas governor to break through with a win. His rise has been fueled by evangelical and religious conservatives who constitute a sizable bloc in Iowa.
He will face tougher going in New Hampshire, where there are fewer evangelicals, and he has lingered well behind Romney and Arizona Sen. John McCain in polls.
Romney, a former governor of Massachusetts who has had to justify his Mormon faith during the campaign, launched aggressive advertising campaigns against Huckabee and McCain in recent weeks.
Iowa's opening contest in the nominating battle has traditionally served to winnow the presidential field of laggards and elevate some surprise contenders.
Record turnout was expected for the Democrats, surpassing the 124,000 Iowans who participated in 2004. Republicans could challenge their record of 87,000 caucus participants in 2000.