Gallup’s tracking poll shows GOP presidential hopeful Mitt Romney overtaking rival Rick Santorum nationally, after a tumultuous February that saw the presumptive front-runner trail by double digits in many national polls.

Numbers released Sunday show Romney with the support of 31 percent of likely GOP voters with Santorum at 29 percent. Former House Speaker Newt Gingrich comes in third with 15 percent support.

{mosads}Support for Romney has surged nationally; last week Santorum held a 10-point lead over the former Massachusetts governor in Gallup’s survey. Saturday’s Gallup five-day average showed Santorum only up 1 point, with 31 percent support to Romney’s 30 percent.

Santorum had surged to the top of polls nationally and in key states after he rode a trifecta of victories in the Minnesota, Missouri and Colorado primaries earlier this month. 

Romney also fell behind in polls for Tuesday’s Michigan primary but, aided by a fundraising advantage and superior organization, has battled back. 

Polls released Friday showed him edging ahead of Santorum in his home state, where he grew up and where his father served as governor.

A Mitchell Research-Rosetta Stone survey showed Romney up in Michigan with 36 percent support from likely voters, followed by Santorum at 33 percent, Rep. Ron Paul (Texas) at 12 percent and Gingrich at 9 percent.

A poll from conservative polling outlet Rasmussen also showed Romney with the lead, holding 40 percent support to Santorum’s 34 percent support.

Romney also led in Arizona’s polls, but Santorum is within striking distance. A poll from American Research Group showed Romney ahead of Santorum in the state 39 percent to 35 percent. Gingrich earned 15 percent support, trailed by Paul at 11 percent. Arizona also holds its primary on Feb. 28.

The Gallup poll also shows Romney leading President Obama by 4 percentage points. 

Gallup’s survey finds Romney garnering 50 percent support in a hypothetical match-up with Obama to the president’s 46 percent. Romney’s support is up 2 percent from the organization’s last survey of a hypothetical general election between the president and the former Massachusetts governor. 

Santorum, a former Pennsylvania senator, draws 48 percent in a hypothetical match-up against Obama, compared to the president’s 49 percent. 

The Gallup survey has a four-point margin of error.