FL. Mandel might perform wore than Rubio but he has a higher floor of solidly Republican voters, and that floor makes him safe. Ryan has a <5% chance; Demings could do a little better.
Still, it’s worth remembering that Democrats did win a downballot office in Ohio in 2020 - the partisan race for an OH Supreme Court seat. Democrats in Ohio have not quite gone the way of the dodo, although they’re not going anywhere good in this midterm.
Note that until now party labels were not on the ballot for the Ohio court.