I'd certainly support her, since 1) diversity 2) she's been a solid mayor and I think she's handled this situation pretty well and 3) it would start a tradition of Baltimore Mayors knocking off one-term Republican Governors.
Why?
Well after seeing the events of yesterday I retract that somewhat, but I do think she's done the best she can possibly do. When this kind of thing breaks out there isn't a whole lot the officials can do and there are really no ways to come out of it in good shape. At the very least it's been handled much better than the Ferguson fiasco (though an orangutan could have handled Ferguson better than it was in reality, so it's not that much of a compliment, but it is still something that works in Blake's favor). Though if Cummings runs for Senate, could she run for his House of Reps seat? Suburban Marylanders statewide might not vote for her but she could certainly still win in the House.