Rick Santorum's late surge and Ron Paul's dominance among young voters and independents combined to undercut Mitt Romney's front-runner status in the GOP presidential field Tuesday night.

The tight three-way finish in the Iowa caucuses showed no clear favorite. Early Wednesday morning, with 100 percent of votes tallied, Santorum and Romney were statistically tied with 25 percent each -- and Romney winning by a mere eight votes out of 60,015 cast between the two men. Paul had 21 percent of the approximately 121,000 total votes cast.

"This is not good news for Romney, and points to a prolonged contest," said veteran GOP strategist Roger Stone. "He needed to be first, but he got fewer total votes than he got four years ago."

Daniel Smith, a political science professor at the University of Florida, said, "Santorum will be the front-page news. Equally so, Romney has not separated himself from the pack, even though his affiliated super-PACs poured a lot of money in hoping to seal the deal in Iowa."

Paul and Santorum exposed Romney's thin support, with Paul garnering 48 percent of independent voters and a plurality of young voters.

Santorum grabbed the largest share of those who described themselves as social conservatives or tea party members. The former Pennsylvania senator also won one-third of late deciders, suggesting he has the most momentum heading into next Tuesday's New Hampshire primary.

Having campaigned in all of Iowa's 99 counties, Santorum on Tuesday night pledged to spend six days stumping the Granite State, attacking Romney.

Newt Gingrich, smarting from a fourth-place finish, also vowed to turn up the heat on Romney, who he branded "a timid moderate."

Among the second-tier candidates, Gingrich faded to 13  percent. Rick Perry captured 10 percent and announced late Tuesday he is reassessing his campaign and heading back to Texas. Michele Bachmann finished sixth with only 5 percent but did not indicate she is discontinuing the campaign.

Smith predicted that Gingrich's free-fall in Iowa will tarnish his standing in Florida, where recent polls showed him running first or second behind Romney.

"Gingrich's lead will evaporate in Florida as quickly as Herman Cain's, and parallels what happened to Rudy Giuliani in 2008," the professor noted.

Smith forecast that Perry's supporters will eventually shift to Romney, whose campaign started airing ads in Florida this week.

Though Romney is expected to easily win New Hampshire, Florida-based tea party leader Patricia Sullivan says the former Massachusetts governor has little support in the tea movement.

"Romney is not an option," Sullivan declared Tuesday night.

Sullivan, who had supported Cain before he quit the race, said she could "live with" Santorum or Gingrich. But she cautioned that tea partiers have yet to coalesce behind any one candidate.

Stone believes that Romney's support is "capped" as votes from fallen candidates "redistribute to other conservatives." An Internet-based Republican group, NotMittRomney.com, says it is counting on Florida to winnow the field to one anti-Romney candidate.

Blaise Ingoglia, vice chairman of the Republican Party of Florida, said his main takeaway Tuesday night was that "winning the Iowa caucus doesn't necessarily mean you're going to win the nomination."

Indeed, the 2012 contest could mirror what happened in 2008. That year, Mike Huckabee, an economic populist like Santorum, won Iowa and John McCain finished fourth. Then McCain rebounded to win Florida and the Arizona senator cruised to the nomination.

"The big prize is Florida. The test is to have the organization and the money to win," Ingoglia said.