Rick Santorum has taken the lead nationally in the Republican presidential race for the first time, a new poll showed.

Less than a week after besting Romney in primary contests in three states, Rick Santorum has a 15-point lead on the former Massachusetts governor, according to a national poll released Saturday by Democratic firm Public Policy Polling. Recent polls had shown Romney up about 10 points on Newt Gingrich, his nearest rival.

Santorum leads Mitt Romney 38 percent to 23 percent in the new poll, while Gingrich is in third place with 17 percent. Ron Paul comes in last with 13 percent.

This is the first major national poll to show Santorum in the lead. The closest he had come previously was after his surprise win in Iowa the first week of January, but even then, Romney performed 10 points better than Santorum nationally.