AMES, Iowa — While most of the attention heading into this weekend's Iowa straw poll is on Michele Bachmann and Tim Pawlenty, lesser-known Republican presidential candidates are working equally as hard to pull off a surprise.
It may be possible.
"At this point, the straw poll is a wide-open situation," said Iowa Gov. Terry Branstad, who warned against buying into the conventional wisdom that there are any front-runners for the nonbinding vote.
The outcome can indicate both the popularity of the candidates as well as which campaign has the strongest organization in Iowa, the state that launches the presidential nominating season.
Often, overlooked candidates like businessman Herman Cain, former Pennsylvania Sen. Rick Santorum and Texas Rep. Ron Paul have focused for months on the quiet business of grass-roots organizing. That could pay some dividends in an organization-driven event like Saturday's test vote, where the challenge is delivering backers to an event.
Any one of the lesser-known candidates presumably could end up being spoilers by siphoning away supporters who otherwise would go to Bachmann, who is looking to keep her momentum going with a victory Saturday, or Pawlenty, who is languishing in polls and hoping for a boost with a strong showing.
At the same time, the outcome could be skewed by votes cast for others who aren't aggressively competing but who still are on the ballot – namely GOP front-runner Mitt Romney – as well as for Republicans who could be written in by backers, like Texas Gov. Rick Perry or former Alaska Gov. Sarah Palin, who was to visit the Iowa State Fair on Friday.
"There is a deep level of activity from candidates who are going to have a presence at the straw poll," said Matt Strawn, chairman of the Iowa GOP, which puts on the straw poll to raise money. "There's more uncertainty about the results of this straw poll than any in recent history and that tells me there are a lot of candidates out there hustling."
Of the lesser-knowns, Paul is clearly among those banking on the power of quiet organizing to engineer a surprise. He's brought on respected Republican strategist Drew Ivers to head his Iowa effort and he's shelled out $31,000 for the prime spot for his tent to entertain backers during the daylong event.
"Paul supporters are exceptionally loyal to him," said GOP strategist Bob Haus.
All candidates are out to earn respect for their grass-roots organizing.
"We have three campaigns that have spent well over a million dollars each," said Santorum. "We are not one of those campaigns."
He added: "If we can be in the top five, it shows that our grass-roots effort is really working."
Santorum spent Thursday eating breakfast with activists, and he said he sees plenty of evidence that his grass-roots campaign is making gains.
"They've kicked the tires and they feel comfortable with me," he said.
Regardless of the outcome, Santorum said, he's in the race until next winter's precinct caucuses.
Cain, who has some support within the tea party, has said he needs to finish in the top three in the straw poll.
Strategist Danny Diaz said the lesser-knowns are out to prove to the Republican electorate that they are worth giving consideration. "They can maintain some relevance," he said, "and they need to demonstrate to donors that they are viable."
RELATED VIDEO: Below, highlights from Thursday night's GOP presidential debate in Iowa.