|Libertarian congressman Ron Paul, second left, came in a close second to Bachmann, far right [Reuters]
US Congresswoman and Republican presidential candidate Michele Bachmann has narrowly won the Iowa straw poll, in an early boost for her campaign for the White House.
Bachmann came out on top after campaigning hard in the heartland state, with 4,823, or 28.5 per cent, of the 16,892 votes cast in the early test for Republicans.
Libertarian congressman Ron Paul came in a close second with 4,671 votes, followed by former Minnesota governor Tim Pawlenty in third with 2,293.
Saturday's result comes five months before Iowa holds the caucuses that kick off the Republican nomination season.
The position breathes some life into Pawlenty's push for the nomination, as he had been trailing in the polls, although some observers pointed out he needed a sterling Iowa performance to maintain a healthy campaign.
Texas governor Rick Perry, who formally kicked off his campaign earlier on Saturday - leaping immediately near the head of the crowded field - was not in the running for the Ames poll, but still garnered 718 in write-in votes.
Perry's write-in tally was notably ahead of the other front-runner, former Massachusetts Governor Mitt Romney, who received only 567 nods - though he has not spent much time in Iowa, preferring to focus on other states.
John Nichols, a political writer for The Nation magazine, told Al Jazeera that it was "not entirely surprising that Bachmann won, seeing as she was considered the star of the Iowa polls, but it would come as unpleasant news for Pawlanty who staked an immense amount of effort and energy in doing well in these polls.
"This loss could actually knock him out the race."
Explaining what he thought was the underlying message of polls, Nichols said: "These Republicans believe Barack Obama is vulnerable, so they are very serious about these races; spending tens of millions if not hundreds of millions.
"So they are not playing games here - this is not a family feud. This is a really serious fight to get the nomination."
Asked who he thought Obama could most easily beat at the polls, Nichols replied: "That guy is a girl - Michele Bachmann.
"They would love to run against Bachmann because they believe of all the candidates, she is the one that most frightens the middle. She seems too extreme.
"Between Perry and Romney it's a little more complex but they would fear Perry more because he is a sitting governor with a current record.
"As it happens, the Texas economy is a little bit better than the rest of the country; so they would prefer not to run against him and would see Romney as somewhat more vulnerable."
The Iowa poll is seen as a key early indicator for how Republican candidates will fare in the state's caucus early next year, and tends to favour conservative candidates who can electrify their activist base.