It is my belief that presidential endorsements do matter. While every person is entitled to his or her own belief and opinion, there are always the select few that remain on the fence. Something like a presidential endorsement can easily sway the opinion of those already trying to decide, or even change the opinion of a current supporter of that president.
Who better to back you than the president of the United States. The president was elected by majority vote and carries a source of authority that is unmatched in public view. When the president endorses you it shows that your ideals are in line with that of the majority of the country. It holds value when you say people should respect my views, after all even the president does.
I think overall that the President's opinion does carry a lot of weight and when the President endorses someone it does give them a boost among the base and may convince some of the undecideds to that candidate, so overall I think that Presidential endorsements can change the outcome of a close election.
it is a fact that presidential endorsement dont matter "The strength of the Tea Party movement is that millions of people are making up their own minds," Russo said. "I don't think there's a silver bullet in the sense if one person endorses, everybody will jump."
David Karol, an associated professor at the University of Maryland, is among those political experts who say a single endorsement at this stage in the GOP race doesn't matter.