A third poll this week shows the Ohio Senate race up for grabs, as Republican Rob Portman and Democrat Lee Fisher fight for the open seat being vacated by retiring Republican George Voinovich. Rasmussen finds Portman leading by 4 points -- still within the margin of error but a change from the week's earlier polls that both found Fisher up 2 points.

Portman 43 (nc vs. last poll, June 3)
Fisher 39 (-4)
Und 13

RCP rates this race a Toss Up. Along with Florida and Missouri, Ohio is one of three open Republican seats RCP has in that category.

The survey of 500 likely voters was conducted June 29 with a margin of error of +/- 4.5%.

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