Over at RCP, Charles Lipson provides a useful summary of the issue and makes a reasonable suggestion for how to proceed.
He summarizes what we know, including the fact that no credible source gives any evidence for the idea that Trump didn't win, and then states that this is a matter of election integrity which everyone should be concerned about. He proposes something like the 9/11 commission to investigate and highlight areas of vulnerability.
Overall, I think he's on the right track. One problem for me is that I increasingly don't trust any part of the US government to conduct a reasonable, non-partisan investigation. The failure to indict Clinton was a big blow to that confidence.
Is there any part of the government we can really trust to do the right thing anymore? Or am I being uncharitable?