TALLAHASSEE (CBSMiami/AP) — In a sign of support from those who put him into the Oval Office four years ago, President Barack Obama has regained his lead over Mitt Romney in the latest Quinnipiac University poll of Florida voters.

In the telephone survey from June 12th-18th of 1,697 random registered voters, 46 percent said they would vote for Obama compared to 42 percent who said they favored Romney.

This was a change from last month’s poll when Romney led Obama 47 percent to 41 percent. The president benefited most from a big swing among independent voters who preferred Obama by a 46-37 margin. A month ago, independents chose Romney by a 44-36 margin.

“It’s worth noting that the last Quinnipiac University Florida poll was on the heels of the president’s backing of gay marriage, which might have hurt him,” pollster Peter Brown said Thursday. “This movement reflects that uncertainty among voters who are up for grabs.”

Obama was backed by young voters, minorities and women while Romney was favored by white and older voters.

“Romney is not well-defined in the minds of many voters, especially those in the middle,” Brown said.

The poll also shows U.S. Rep. Connie Mack IV far ahead of the field in his bid for the Republican nomination and a shot at unseating two-term U.S. Sen. Bill Nelson.

Mack, the son of former U.S. Sen. Connie Mack and great-grandson of the legendary baseball owner and manager with the same name, received 41 percent while no other Republican candidate was in double figures.

The poll showed Nelson with a 43-39 edge on Mack if the election were held now with 18 percent undecided.

Mack is trying to regain the seat won his father 24 years ago when the elder Mack defeated Democratic nominee Buddy MacKay in the closest U.S. Senate race in Florida history.

Nelson was elected in 2000 when he defeated Republican Bill McCollum. He was easily re-elected in 2006 when he faced former U.S. rep. and Florida Secretary of State Katherine Harris.

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