As the clock ticked toward midnight in Sioux City, Iowa, Mitt Romney burst into a smallish meeting room at the Stoney Creek Inn with a broad smile on his face. “My goodness!” he said, briskly walking and talking. “We should have rented a bigger room! Isn’t that something?!”

Not only was the place packed with standing, clapping likely Iowa caucusgoers, but the atrium outside the room held three times as many people clamoring to get in to see the former Massachusetts governor.

Romney had a lot more to smile about than just the healthy turnout at his third town-hall meeting of the day. Just three days before the Iowa caucuses, he suddenly had a better-than-even chance to win the contest he lost in a rout to Mike Huckabee in 2008 and pundits have written off ever since.

The highly predictive Des Moines Register poll released Saturday night showed Romney poised to win the Tuesday caucuses with 24 percent of the vote, Rep. Ron Paul in striking distance at 22 percent, and former Pennsylvania senator Rick Santorum taking over third place back at 15 percent.

A win for Romney among the evangelical-heavy Iowa voters, combined with a victory in next week’s more liberal New Hampshire primary, would seem to make him nearly impossible to beat for the five other Republicans who are battling among themselves to become the anti-Romney, but running out of time and money to actually edge him out for the nomination.

Surveying the crowd in Sioux City, Romney launched into an almost soaring speech about the virtues of the nation he says he wants to restore, not remake.

“The next election isn’t about just picking the next president,” he said. “It’s about the soul of the country.”

He peppered his speech with declarations of loyalty and patriotism that would be cringeworthy for their corniness if he didn’t seem to believe them so genuinely.

“One of my favorite songs is ‘America the Beautiful,’” he said with a smile. “Do cornfields count as amber waves of grain?”

Speaking of the recession the country has struggled through for the last three years, he promised, “This is a detour, not a destiny, for America.”

Romney’s visit to the significantly conservative Sioux City area, nearly four hours away from Des Moines, was just a piece of his campaign’s recently adopted all-in strategy for the Hawkeye State after months of ambivalence over committing to, and possibly losing, the GOP stronghold.

But after a summer in which one conservative candidate after another crested and crashed, the Romney campaign has made the calculation that the next, and last, candidate to rise in Iowa should be their own.

The decision, it seems, is about to pay off as the GOP faithful come around to the one person they seem to agree could beat Barack Obama in November.

But a calculation of victory hasn’t been the only force at work in Iowa lately. With smiles, nods, clapping, and cheering, they listened Saturday to Romney’s vision of what he said he wanted for the country—a balanced budget, opportunity for kids, a safety net for seniors, and an ideal that people would be proud of again.

For someone accused of pandering to Republicans, Romney’s speech was remarkably devoid of any mention of God, guns, gays, Ronald Reagan, or any of his five opponents. When he spoke of President Obama, he stuck to the president’s policies and what he called Obama’s effort to create an “entitlement state,” but avoided any talk of Saul Alinsky, socialism, and the other buzzwords that talk-radio hosts associate with Obama these days.

Even without the red meat and fighting words, the response from the assembled GOP voters was unmistakably positive.

Mel Adema, a businessman in Sioux City who has been courted by nearly all of the campaigns but has not committed to any candidate, thinks Romney will win Iowa in what he called “a real horse race.”

“Mitt looks really strong,” Adema said. “I think people see him as very levelheaded, very calm. People in Iowa cling to people like that who are quite homey, quite bright, those types of things.”

As true as that is, Romney also hasn’t gotten to the front of the Republican pack at precisely the right moment on gee-whiz alone. Behind his perfectly timed rise has been the swift, hard fall of Newt Gingrich, the frontrunner until the middle of December, when Restore Our Future, a super PAC associated with but not controlled by Romney, launched a campaign of negative television ads against him, including more than $3 million worth that hammered Gingrich, ironically, for a series of flip-flops on issues like global warming.

Locally, Gingrich peaked at 31 percent in a University of Iowa poll three days before the ads began in early December. The Des Moines Register poll released Saturday showed him in fourth place, with 12 percent, and just 1 point ahead of Texas Gov. Rick Perry, whose multimillion-dollar war chest alone ensures he’ll outlast Gingrich if he wants to.

Romney’s lead with just 24 percent leaves raises the question of why 76 percent of Iowa Republicans aren’t on board with him yet, and whether they’ll get behind him in a general election if he takes the nomination.

But the signs for Romney seem to be getting better every day, especially among conservatives. Despite assumptions in the media that Iowa’s evangelicals would never support him, plenty of members of Sioux City’s Central Baptist Church came out Saturday to see him and left planning to caucus for him on Tuesday.

Paul Baker, who supported Mike Huckabee in 2008 and Tim Pawlenty earlier in this campaign, liked what he heard at the Stoney Creek Inn and said he would absolutely caucus for Romney on Tuesday. “He’s very intelligent, very presidential, he has a vision. He’s Reaganesque,” Baker said. Another thing Baker likes about him? “Romney can win.”