His approval rating, meanwhile, has dropped from 48 percent in mid-April to 41 percent now, according to the poll, released Wednesday by Survey USA. The poll has a margin of error of 4.1 percent.

"People are paying more attention now than they were a few months ago," says a Brown campaign aide. "We know Sherrod's name recognition is only going to grow. And as they meet him, they're [getting] on board."

The DeWine campaign was unsurprised by the poll. "There's going to be a number of polls released from now until Election Day, and some are going to be better than others," says campaign spokesman Brian Seitchik. "We've always said this is going to be a very close election."

A series of recent Ohio polls have painted starkly different pictures of the race. A survey conducted earlier this month by local television stations shows Brown beating DeWine, 48 percent to 39 percent. But a University of Cincinnati poll conducted last month had DeWine with a 10-point lead.

Seitchik says voters will become less supportive of Brown as they learn more about him in coming months: "They'll become familiar with his 14-year record voting against tax cuts, intelligence funding, and defense appropriations." DeWine is building his re-election strategy around contrasting his Senate record with Brown's 14-year House record. –Dan Gilgoff