In fact, there are no objective indications that Trump’s rallies have any relation to boosting his support, with some suggestion they are just as likely to energize his opponents’ supporters as they are his own.

In a study of the 2016 race, researchers looked at fundraising on the day of a Trump event and found that in the regions where the events were held, Clinton saw a significantly greater uptick in donations than Trump.

“It does help a little bit on the Republicans’ side, but it gets the same counter-mobilization on the Democrats’ side, if not more,” said Boris Heersink, an author of the study and a professor of political science at Fordham University.

A separate study of the 2018 midterm elections found a similar effect, where Trump’s endorsement of congressional candidates in some areas sparked a backlash effect that was ultimately detrimental to those he was backing.