Michele Bachmann won the Iowa straw poll last night in the first big test of the 2012 Republican presidential campaign, as Texas Governor Rick Perry launched a White House bid that could reshape the race.
Ms Bachmann, a representative from Minnesota, narrowly edged out Ron Paul and rolled over the rest of the field to capture the non-binding mock election, an early gauge of strength in the state that holds the first 2012 Republican nominating contest.
Tim Pawlenty, a former Minnesota governor, finished a distant third, dealing a setback to his struggling campaign.
"This is the very first step toward taking the White House in 2012," Ms Bachmann told a small crowd of supporters outside her campaign bus on the straw poll grounds. "Now it's on to all 50 states."
In South Carolina, Mr Perry formally jumped into the race with a blistering attack on President Barack Obama.
"We cannot afford four more years of this rudderless leadership," he told a conference of conservatives, promising to reduce taxes, regulations and government intrusion in people's lives.
The straw poll and Mr Perry's campaign launch, coming less than six months before Iowa's nominating contest, promised to reshuffle the Republican field fighting for the nomination to challenge Obama, a Democrat, in 2012.
Mr Perry, a staunch social conservative with a strong job creation record in Texas, is expected to immediately vault into the top tier of contenders along with front-runner Mitt Romney. Mr Perry visits Iowa on Sunday.
In the straw poll, Ms Bachmann won with 29 per cent of the vote. Paul, a representative from Texas, was a close second with 28 percent and Pawlenty had 14 per cent.
Ms Bachmann's win adds to her recent momentum and cements her standing in the top tier of contenders. She had shot to the top of opinion polls in Iowa this summer with the support of social conservatives and the fiscal conservative Tea Party movement.