I hope he loses. He should have stayed on path of retirement. He was so rejected, now nothing more than an embarrassment.
I'm a Floridian who has been eminently unhappy with Rubio, but it's not that simple.
If Trump wins and Rubio wins, Rubio may or may not fight Trump's agenda. If Trump wins and Grayson or Murphy win, either will immediately glom on to Reid/Durbin and fight Trump's agenda, and they will have all of the FL MSM on their side, including and especially the local FOX affiliates, Politifacts, and the local cable channel news (Bay News 9, Orlando 13, etc.). I think we have to play the percentages here, hold our nose and give Rubio the seat, since there is no one who is running and is more conservative (or less liberal).
P.S. If Hillary! wins, none of this matters, so let Rubio have the seat, and let's concentrate on keeping HRC out of the WH.