Ohio Lt. Gov. Lee Fisher has opened up a double-digit lead over his rival for the Democratic Senate nomination, Secretary of State Jennifer Brunner, ahead of next week’s primary, according to a Quinnipiac University poll conducted April 22-26.

Of the 987 likely Democratic primary voters surveyed, Fisher was backed by 41 percent and Brunner was the choice of 24 percent. Most of the rest said they weren’t sure of their choice.

Earlier polls had Fisher, the candidate preferred by the Democratic Senatorial Campaign Committee, leading by smaller margins.

This poll was in the field at a time when Ohioans were seeing a lot of Fisher on their televisions.

Fisher hasn’t closed the deal, though. According to the poll, 51 percent of those who identified a preferred candidate said they could change their minds.

The Democratic winner on Tuesday will face former Rep. Rob Portman, who is unopposed in the Republican primary. Sen. George Voinovich (R) is retiring.