Ohio is still a pro-Obama state, but by a narrower margin, according to a poll by the national firm Public Policy Polling.
The PPP shows Democratic President Barack Obama leading Republican Mitt Romney 47 percent to 44 percent, a statistical tie because the polling sample had a margin of error of 3.8 percent.
Obama was ahead of Romney 49-42 in PPP's early May poll.
PPP, a Democratic pollster which maintains its polls are highly accurate, said in a news release Tuesday that Obama’s decline is mostly among white voters.
Obama and Romney were basically tied among white voters earlier in the year, but Romney now has an advantage of 49 percent to 42 percent. White Democrats favored Obama 89-6 in early May. Now they favor him 78-16, according to PPP.
“Obama remains a modest favorite in Ohio but his struggles with white voters are starting to make it look dicier for him,” PPP said in prepared statement.
Also, Obama’s job performance approval rating in Ohio has dipped to 44 to 51. Earlier this year, voters in Ohio were evenly split, at 48 percent.
Romney isn't doing any better, with a favorable-to-unfavorable rating of 35-54.
“With Obama’s approval numbers where they are he would almost definitely be trailing if the GOP had a top notch candidate against him - but it really just doesn’t,” PPP said.
PPP says Obama’s “tenuous” lead is based largely on his strong support among three core constituencies — African Americans (93-6), young voters (54-36), and women (52-41).
The pollsters also looked at the potential impact of Ohio U.S. Sen. Rob Portman as Romney's running mate, and didn’t find any improvement in Romney's numbers if Portman joins the ticket.
A spokesman for the Republican National Committee pointed to data in the PPP poll that showed Obama’s support weakening among independents and women.
In May, Obama led Romney 43-40 among independent voters. In the most recent poll, the two were tied at 42 percent.
In May, 41 percent of female voters disapproved of Obama's job performance. In late June, that number was 47 percent.
The most recent poll was taken June 21-24 and surveyed 673 voters.