As an anecdotal aside, I attended the Trump rally in Pennsylvania last Saturday night. The Secret Service presence there was no different than you would have for a sitting president. Not only were there dozens of Secret Service agents checking everybody in with "airport level" security checks but just before Trump came out to speak, additional Secret Service agents ringed the entire podium area.
No other former president ever packed a 10,000 seat arena to the rafters that I can recall - just to hear him speak for an hour or so - not even Reagan.