I doubt it.I do think that's possible...but if I had to go with just one I'd go with someone anyone shooting Trump.
Trump will have better security as President than he had as a Candidate.
He also won't be spending his own money on venues so those can be more secure as well.
People will be arrested for threats (every President has had attempts on their life for decades now) but none will get as close as what happened in the summer.
I would be genuinely shocked if there was another incident.