A surprising national poll released Tuesday found Texas Rep. Ron Paul surging to second place in the GOP presidential field, coming within eight percentage points of front-runner Mitt Romney.

The Reuters/Ipsos poll results show Paul at 21 percent nationally, with Romney, the former Massachusetts governor, at 29 percent.

Former House Speaker Newt Gingrich scored 19 percent support in the poll, conducted Feb. 2–6, while former Pennsylvania Sen. Rick Santorum took 18 percent.

Although national polls are largely insignificant in a primary season where individual states are of crucial importance, they do indicate trends in voter preferences.

Reuters/Ipsos found that despite big wins by Romney in Florida and Nevada, his popularity actually declined since early January. Meanwhile, Paul’s support grew by five percent.

Romney “still hasn’t really convinced all the Republicans across the country that he’s the guy to get behind,” said Ipsos research director Chris Jackson in a statement.

Gingrich’s support slipped slightly, while Santorum’s support also grew by five percentage points since early January. (RELATED: Full coverage of Ron Paul’s campaign)

Paul’s campaign seized on the poll results as evidence of the libertarian favorite’s growing appeal.

“This poll further illustrates that Ron Paul is emerging as the real conservative alternative to Mitt Romney,” said Paul campaign chairman Jesse Benton, “and that he can also obtain the needed support from Independents and disenfranchised Democrats to defeat President Obama in November.”

The poll results significantly reflected only the preferences of self-identified Republican voters. In several states, independent and Democratic voters can also cast ballots in GOP primaries — constituencies seen as favorable to Paul.

Paul supporters have frequently griped that national telephone-based polls underestimate the Texas congressman’s support, because many of his supporters are young and do not have land-line phones.

The Reuters/Ipsos poll, conducted by telephone, featured 405 Republicans, and had a calculated margin of error of 4.9 percentage points.

Paul’s best performance so far this season was a 23 percent showing in New Hampshire, closely followed by 21 percent in Iowa and 19 percent in Nevada.

Most national polls find Paul attracting far less support, with national Rasmussen and Gallup polls released Tuesday pegging his support at 11 percent.

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