We'll never know, but his work in swing states, especially Pennsylvania surely changed some minds and swayed some essential independent voters. The election could have had a very different result if not for the votes for a very small number of people in a handful of swing states. It wouldn't have taken much for it to have gone the other way.
Discussion
I think I read she did really bad, like record breaking bad. I think it would have taken a lot lol.
She did very poorly. But the end tally wasn't the healthy win that it looked like on election night. Considering the vote gap in the few states that mattered, a very small number of votes would flipped those states in the other direction. She could have done poorly and won if a relative few votes went the other way.