Republican presidential candidate Mitt Romney squeaked out a victory in Iowa's first-in-the-nation nominating contest on Tuesday as little-known rival Rick Santorum rode lingering conservative unease to a surprise second-place finish.

Romney edged out Santorum by only eight votes, winning by 30,015 to 30,007, the state Republican Party announced.

As the Republicans headed for their next contest in Romney stronghold New Hampshire, the result solidified his frontrunner status in the battle to pick a challenger to President Barack Obama in November's election.      

At the same time, it underscored Romney's inability so far to secure the trust of his party's conservative wing and consolidate support ahead of what is likely to be the most expensive presidential election campaign in history.     

Santorum, a former Pennsylvania senator who until recently has been little more than an afterthought in the race, was the latest candidate to benefit from Romney's weakness, which has allowed a succession of rivals to challenge him.

"Game on!" Santorum declared to cheering supporters as votes trickled in after the agonisingly close contest. "People have asked me how I've done this," he said. "I survived the challenges so far by the daily grace that comes from God."

Santorum and Romney, a former Massachusetts governor who has relentlessly attacked Obama for his "failed presidency" and touted his experience as a businessman, each took 25 percent of the vote. Ron Paul, a Texas congressman, came in third place with 21 percent of the vote.

After the bruising contest, at least one candidate, Texas Governor Rick Perry, indicated his presidential bid may be over. "I've decided to return to Texas, assess the results of tonight's caucus, determine whether there is a path forward for myself in this race," Perry said after a disappointing fifth place finish.

With deep reserves of cash and a strong campaign infrastructure, Romney will emerge from Iowa in a stronger position than his rivals. A favorite of the party's business wing, Romney holds a commanding lead in next Tuesday's New Hampshire primary and has the resources to compete in bigger states like Florida at the end of the month.

A Republican official said Senator John McCain, the party's 2008 nominee, will endorse Romney on Wednesday. - Reuters