Republican presidential candidate Rick Santorum has a thin lead in Ohio over GOP frontrunner Mitt Romney heading into Super Tuesday, according to a new poll released Friday.

Santorum, the former Pennsylvania senator, pulled in 35 percent of those polled by Quinnipiac University, while Romney, the ex-Massachusetts governor, received 31 percent.

Santorum's lead is within the poll's 4.3 percent margin of error.

Of the 517 likely Republican Ohio primary voters polled by Quinnipiac, 17 percent said they will vote for former House Speaker Newt Gingrich while 12 percent favor U.S. Rep. Ron Paul (R-Tex.)

In Ohio, the race between Santorum and Romney is tightening. In an earlier poll by Quinnipiac, Santorum led Romney 36 percent to 29 percent in the Buckeye State.

The survey also showed about a third of Ohio primary voters may change their minds.

Ohio is one of 10 states holding primaries or caucuses March 6, known as Super Tuesday because of the large number of convention delegates at stake.

At this point, the Buckeye State is too close to call and is clearly a two-man race between Sen. Rick Santorum and Gov. Mitt Romney, said Peter A. Brown, assistant director of the Quinnipiac University Polling Institute. A third of the electorate say they still might change their mind. With five days until Super Tuesday, they certainly will be exposed to enough negative television ads to provide fodder for those who might want to switch--or switch off.