The reason these sorts of endorsements matter is about their distribution.
On the top level, the media is more likely to cover such an event, and having local media coverage of a national candidate is always a good goal. The press tends to be much friendlier, and it reaches people who are statistically more likely to be undecided.
On another level, the other great value of having local politicians behind you is they have their own contact and distribution lists. So, when you get an e-mail or call sent to voters who vote, which is who the State Senator will have collected, telling them Ron is the real deal, that's the sort of publicity you can't buy.
The circus is annoying, but endorsements matter because they get exposure. Not because they decide votes.