I suppose if I felt they were doing it in good faith the only thing they would have to lose is time, effort, and money. But the fact that Trump has said all of the problematic ones were in states in which he didn't win, and not a single one was in his favor, tells me their investigation would not be in good faith.

Polls have shown (sorry, don't have them now) that Americans generally agree more with Democratic policies that Republican ones if those policies are not presented while attached to a party. Right now the Republicans are basically hanging on in this country through a combination of identity voting, gerrymandering, religion, and voter suppression. They fight efforts to make it easier to vote, such as a national holiday for voting, vote by mail, voting without ID, allowing previously convicted felons to vote, etc. Although it's been proven time and time again that there really is not voting fraud, they'll probably find a couple of cases, use them as an example, and clamp down to make it harder for people to vote overall.