Too late to assassinate Biden now, they would've had to get it done yesterday. However, the fallout might hasten the urgency of the Democrats about changing things up. They're going to need to get way, way outside the frame of "Ha ha, this is what you get for not supporting gun control" to cut through this.
I don't think the identity of the shooter will prove to be too relevant, unless he's a migrant. Other than that, Fox News and the rest will readily be able to paint whoever it was as an over-intellectual outsider to normative society.
