On the eve of the only Democratic presidential debate in the Buckeye State, two new polls released this morning show that Sen. Barack Obama is whittling away at Sen. Hillary Clinton’s lead in Ohio.

The Illinois senator has chopped 10 points off Clinton’s lead in just 11 days in the Quinnipiac Poll, now trailing 51 to 40 percent,

The Ohio Poll, conducted by the Institute of Policy Research at the University of Cincinnati, gives Clinton an 8-point lead, 47-39. The Ohio Poll had not conducted a survey in recent weeks.

Both polls also give Sen. John McCain of Arizona a wide lead in Ohio over former Arkansas Gov. Mike Huckabee.

“Sen. Clinton’s lead remains substantial, but the trend line should be worrisome for her in a state that even her husband, former President Bill Clinton, has said she must win,” said Peter Brown, assistant director of the Quinnipiac University Polling Institute, in a release. “A week is an awful long time in politics to be playing defense, but one thing going in her favor is that she is viewed more favorably than is he by Ohio likely Democratic primary voters.

“Sen. Obama, to no one’s surprise given his momentum nationally, has made inroads, especially among some of Sen. Clinton’s softer supporters,” Brown said. “If she is to stop his momentum in Ohio, she must retain her margins among her core backers – women, older voters and those lower on the social-economic and education scale.”

The poll showed Clinton leading by 21 points on Feb. 14.

The survey also tested Ohioans’ reactions to possible running mates from the state for McCain, who has the GOP nomination virtually locked.

If he were to pick Sen. George V. Voinovich, it would actually hurt McCain among Ohio voters, the poll found; his support would drop by 9 percent. But 70 percent say having the former Ohio governor on the ticket would make no difference.

Choosing Cincinnati’s Rob Portman, a former Ohio congressman and U.S. Trade representative, also would be a negative, with a net 7 percent saying it would make them less likely to back McCain. Still, 76 percent say putting Portman on the ticket would have no impact.

The telephone poll from Monday through Saturday by the Connecticut university of 1,853 Ohio registered voters has a margin of sampling error of plus or minus 2.3 percentage points. The error margin among the 741 likely Democratic primary voters is plus or minus 3.6 points.

The Ohio Poll telephone survey from Thursday through Sunday involved 529 Democratic likely voters with an error margin of plus or minus 4.3 points.