DES MOINES, Iowa — Ron Paul ended his speech abruptly, without as much as a fist pump on the final day before the caucuses. Reporters who were jammed into a hotel conference room looked at each other asking, is that it?
That was it, and Paul's supporters loved it. "Ron Paul! Ron Paul! Ron Paul!" they shouted as he left the stage at the Des Moines Marriott on Monday.
Paul has been breaking with convention throughout the Republican race for president and today, he could upend it again.
"There's energy and it's overflowing and it's big," said Paul's son, U.S. Sen. Rand Paul of Kentucky. "We're going to win in Iowa."
The caucus outcome will test a central question of whether Republican voters will go with the candidate they think has the best chance to defeat President Barack Obama or the one they feel most passionate about.
"Electability is an issue, but Iowa's got a chance to make a statement," said Fritz Craiger, 54, who said Paul's message of less government and more personal liberty persuaded him to caucus for him.
For all the excitement in the room — which held at least as many reporters as voters — the race remains fluid. Paul's rivals stormed across the state Monday to rally supporters and capture the estimated 41 percent of voters who were still undecided as of the weekend.
Mitt Romney, who has a slight edge in polls, projected confidence in several stops, continuing to assert himself as a general election candidate and to focus on Obama.
"I think people are starting to figure out that this is the guy who is going to beat Barack Obama," Romney's wife, Ann, said in Davenport.
Either Paul or Romney could be surprised by the late-breaking momentum of Rick Santorum, the former U.S. senator from Pennsylvania. Santorum has spent more time in Iowa than any other candidate and is getting a lift from evangelical Christians.
He pulled on an Iowa Hawkeyes sweatshirt in Polk City and tried to counter Romney's attack that he is a career politician. "We are not looking for a chief executive officer for this country," Santorum said, alluding to Romney's business credentials. "We are looking for a commander in chief."
Santorum, who capitalized on his surge with a new TV ad proclaiming he's the best conservative to defeat Obama, got an enthusiastic reception at a Pizza Ranch in Altoona on Monday night. Santorum struggled to make his way through swarms of reporters and some supporters.
Lots of people make light of the caucuses, Santorum said, trying to sound a note of solidarity with Iowans. "You fight to be first," Santorum said. "Lead."
His newfound status brought higher scrutiny, including robo calls attacking him on gun rights and questions about comments he made Sunday about taking black people off welfare. Santorum called the automated calls a false attack and, in an interview, said his welfare comments were out of context. "I believe every American should not be dependent upon government," he said.
Other candidates who had their chance as the Romney alternative were making a last attempt to hang on. Michele Bachmann added a TV ad Monday that played up her roots.
"Born and raised in Iowa, only one candidate has been a consistent conservative fighter, who fought Obamacare, who fought increasing our debt ceiling even as other Republicans were cutting deals with Obama," a narrator says.
TV ads have been nonstop the past week and nearly half have targeted Newt Gingrich, who was leading in Iowa only a few weeks ago. In Independence on Monday, Gingrich conceded their toll.
"I don't think I'm going to win," he told reporters. But Gingrich said he expected to do well enough to continue into New Hampshire (Jan. 10) and South Carolina (Jan. 21), calling it a "victory that I'm still standing."
Florida goes fourth with its Jan. 31 primary.
In Sioux City, Rick Perry referenced poor debate performances that knocked him off the front-runner pedestal. He urged supporters to stick with him, and said Iowa is only the beginning.
"This is the first, let's say, mile one of the marathon and I've run a marathon before," he said. "We'll see who's still running at mile 21. I finished my marathon, and I expect to finish this marathon as well."
Just over 100,000 people are expected to participate in the Republican caucuses, a figure critics point to as Iowa's overstated importance.
A victory by Paul would intensify such talk as pundits and others say he has no shot at winning the nomination due to his foreign policy call for ending U.S. involvement and aid. He has also said the federal government should not regulate illegal drugs, leaving it up for states to decide.
Paul and his backers say those critics and the mainstream media are not sensing a growing national restlessness. "Tomorrow is a very important day," Paul said at the Marriott. "Small in numbers, but a very important message. You carry a lot of weight.''
Information from the Associated Press was used in this report.