(CNN) - With less than a week to go until the primary, a new poll indicates that Ohio Lt. Gov. Lee Fisher holds a large lead over Secretary of State Jennifer Brunner in the race for their state's Democratic senate nomination.
According to a Quinnipiac University survey released Wednesday, 41 percent of likely Democratic primary voters back Fisher, with 24 percent supporting Brunner. But just over a third of the Democratic voters questioned in the poll say they remain undecided and half of those who said they are backing one candidate or another indicate they might change their mind by next Tuesday's primary.
A Quinnipiac survey conducted last month indicated Fisher held a seven point advantage over Brunner.
"Lt. Gov. Lee Fisher has moved into the driver's seat for the Democratic U.S. Senate nomination. For the last year he had held a small lead over Ms. Brunner, but as the primary approaches he has more than doubled his margin. Fisher clearly has momentum on his side," says Peter A. Brown, assistant director of the Quinnipiac University Polling Institute. "Although anything can happen in politics, at this point the race appears to be his to lose. The obvious reason for Fisher opening up the race is that in the last weeks he has overwhelmed Ms. Brunner in television and radio advertising."
The primary winner will face off in November against former Republican congressman Rob Portman, the former budget director under President George W. Bush. The race is to succeed retiring Republican Sen. George Voinovich.
The Quinnipiac University poll was conducted April 22-26, with 987 likely Democratic primary voters questioned by telephone. The survey's sampling error is plus or minus 3.1 percentage points.