A report released by the University of Akron’s Bliss Institute of Applied Politics maps out the Republican sweep of Ohio statewide offices and the open US Senate seat in 2010. The report, which includes maps, show the percentages of votes and turn out compared to the results in 2006. The numbers show that the turn out by Democrats was much lower in 2010 and that helped the GOP with their sweep.
"The pendulum has swung, this time in favor of Ohio Republicans," John Green, Bliss Institute director, said in a press release. "Low voter turnout across the board and a poorly performing state economy contributed significantly to the 2010 Ohio Republican sweep."
Akron U report maps GOP wins in November; contrasts results with 2006
It is clear that there was less voter turnout in 2010 than 2006 in almost every county. The East-West pattern emerges again in this map. There was, in general, less of a drop in voter turnout in the Republican-leaning western regions of the state as opposed to the Democratic-leaning eastern regions of the state. This indicates that Democratic-leaning counties had less-enthused voters compared to those counties that tend to lean Republican. It helps to explain why Democrats did so well in the 2006 state-wide contests and fared so poorly in the 2010 election.
Mapping the Republican Sweep: The 2010 Election Results in Ohio
The report doesn't look at why people voted the way they did but it showed that when a particular party doesn't turn out their candidate loses. It seems that's election 101.

Crossposted from Doug's Views
Update
A couple of comments support my thoughts on this issue that the Dems low turn out was tied to a lack of good PR from the powers that be like the DNC to overcome the drumbeat I kept seeing in my local media that as Wimsical noted "Democrats suck and their ideas are terrible".
Typical Dem voters aren't wonks about policy they go by what they hear and see in the media and don't really dig much deeper than that. The GOP and the press pounded on the negative and the Dems failed to counter it enough. And if the economy had improved enough to be felt on Main St. then the negative press would have been ignored.
Moaning and bitching in blogs like this didn't depress the Dem vote in Ohio.