The incumbent Mike DeWine (R) will face either Northern Ohioan Sherrod Brown (D) , the current Congressman and former Secretary of State, or Paul Hackett (D), the personal injury lawyer and Iraq War veteran from Southern Ohio who nearly upset Jeanne Schmidt (R) in the August 2005 special election in OH-2nd.
Republican challengers John Mitchel (R), William Pierce (R), and David Smith (R) are not a serious threat to DeWine.
Sherrod Brown has raised the ire of Ohio bloggers by cancelling an appearance at Meet the Bloggers, scheduled for Jan. 14, reportedly due in part to hostility toward Ohio blogger Tim Russo.
Rasmussen polling on this race was diaried on DailyKos by JOEL1954 here. The poll was conducted on Jan. 3, with a MoE of 4.5%. DeWine has improved his numbers slightly but the race is still essentially tied; DeWine leads Hackett 43-39 and Brown 45-40.