I think Sherrod Brown is gonna run. Even though he doesn't seem interested in running, he's put out quite a few recent statements in regards to pushing the Democratic Party into a more economically left direction. Maybe it's just me, but I've seen a handful of statements and articles about him recently concerning that topic.
I think he's hesitant right now because he's up for reelection in 2018 (although Trump alone might make his Ohio reelection bid a fairly easy). After the 2018 midterms, I think he'll start testing the waters for a presidential run in 2020.
Sorry, but I highly doubt that. Ohio went the reddest it's been in a generation in the last election. It will take alot more than a Russia narrative to turn it back red.