Earlier quoted context omitted.
Actually, there were claims made about massive voter fraud in the 2016 election: When Trump could not stomach the fact that he lost the popular vote, he claimed that more than 3 million ineligible voters had voted for Clinton and that he had in fact won the popular vote. There was even a voter-fraud commission set up to investigate the claims. They quietly disbanded.
They were not able to acquire any data because Alex Padilla, now temporary Senator replacing Kamala Harris, refused to cooperate. A class case of "we refuse to look for evidence, therefore there is no evidence"
Also why pick on Padilla, why not Jon Husted (Rep, Ohio). What about all the Republican lead states where massive fraud was supposed to have happened? Trump expended no political capital or effort whatsoever on doing anything meaningful about supposed voter fraud, and couldn't even persuade any Republican state administrations he had any credible evidence or reason for alleging it. He just gave up immediately at the first hurdle of being asked what he wanted to do and why. In fact he didn't even pursue this personally, he just delegated it to some flunkies and walked away from the issue until the next election.
How to explain this? It's almost as if he had no credible reason for making the claims and the whole thing was just for show.