WASHINGTON — A new poll shows President Barack Obama has expanded his lead over the Republican frontrunners to double digits, hinting that the GOP presidential candidates have been bruised by a grueling nomination battle.

In the George Washington University-Politico Battleground Poll, Obama beats Mitt Romney by 10 percent and Rick Santorum by 11 percent in a general election match-up.

The survey, released Monday, also finds Obama’s approval rating at 53 percent, a nine-point increase over four months.

Romney remains the top choice of Republican voters, with 56 percent of them saying he has the best shot at winning the general election. In the poll, Santorum trails Romney at 28 percent, with Newt Gingrich and Ron Paul earning 6 percent and 2 percent, respectively.

The George Washington University-Politico Battleground Poll was conducted between Feb. 19 and Feb. 22 by the Tarrance Group and Lake Research Partners. It reached out to 1,000 likely voters nationally via telephone and has a margin of error of 3.1 percentage points.

In an analysis published alongside the poll results, GOP pollsters Ed Goeas and Brian Nienaber of Tarrance, cautioned against reading too much into the survey findings but admitted Republicans must begin coalescing around a consensus candidate.

“Nothing in this latest Battleground poll data is totally unexpected for this stage of a presidential election cycle, and certainly not predictive of the eventual outcome,” the two wrote. “The warning signs are flashing for Republicans, however, and it is certainly a phase of the campaign that Republicans need to bring to an end sooner as opposed to later.”

At a panel discussion of the poll results on the GWU campus Monday, Goeas warned a long slog toward the Republican nomination could hurt the party’s chances at capturing the White House.

“The more this process is extended, the more the messaging is focused inward in terms of primary voters, as opposed to outward,” he said. “I think there certainly has been a great deal of that, complicated by the fact … that the number of the debates has dominated the give-and-take of the campaign.”

Democratic pollster Celinda Lake, a fellow panelist, agreed Republicans have suffered some self-inflicted wounds as they stray from the election’s central issue: the economy.

“This primary process has been very, very damaging because it’s taking Republicans off the major message and allowed us, really, free rein to talk about what’s on voters’ minds,” she said, noting “bizarre views” on social issues like birth control will come back to haunt the GOP nominee in the general election.

The poll reveals voters are mostly split on which party is best positioned to usher in economy recovery.

By a 49-to-45 percent margin, voters said Republicans would handle the economy better than Democrats, according to the results. Voters are less trusting of Republicans when it comes to job creation, resulting in a statistical tie of 48 percent to 46 percent favoring the GOP on the topic.

At Monday’s panel discussion, co-moderator Chris Arterton said Obama has “running room” as the general election campaign nears, noting Monday marked the president’s most promising showing in the Battleground Poll since it was taken in August and November of last year.

But co-moderator and Politico reporter Jonathan Martin pointed to the poll’s finding that only 35 percent of Americans say the country is on the right track — an unflattering number despite Obama’s increasing approval rating.

“It’s nothing to brag about, and we’re certainly not taking any victory laps,” Lake responded. “The point is there’s been improvement, and our line ought to be, ‘We’ve created this many jobs, but that’s not enough.’ We’ve got to keep working on it.”

Monday’s poll echoes previous surveys indicating Obama maintains a competitive edge against Romney and Santorum in a general election scenario. According to RealClearPolitics national polling averages, Obama would beat Romney by more than five points and Santorum by more than six points if the general election were held tomorrow.