A new Des Moines Register poll shows Rep. Ron Paul (R-Texas) would best President Obama in the Hawkeye State if the general election were held today.

President Barack Obama. (Andrew Harrer — Bloomberg)

He is the only one of the GOP White House hopefuls who would defeat Obama in Iowa if the election were held today, according to the survey.

Former senator Rick Santorum (R-Pa.) would be in a dead heat with Obama, taking 48 percent to Obama’s 44 percent, as would former Massachusetts governor Mitt Romney (R), who would take 46 percent to 44 percent for Obama. Both candidates are within the margin of error in a potential matchup with Obama.

The poll shows Obama with a wide lead over former House speaker Newt Gingrich (R-Ga.). Obama would take 51 percent to Gingrich’s 37 percent in Iowa if the election were held today.

Iowa will be a key swing state in the November general election. Obama bested Sen. John McCain (R-Ariz.) by 10 points in the state four years ago, taking 54 percent to McCain’s 44 percent.

But the Iowa Poll suggests that Obama faces a tough task in the fall; the president’s approval rating is underwater in the Hawkeye State, where 46 percent of Iowa adults approve of the job he is doing, while 48 percent disapprove.