According to the article linked below, the answer seems to be Yes for Pennsylvania and Michigan.
- Pennsylvania regulations require the challenger to file for a court appeal and present a prima facie case showing that voter fraud probably occurred. But nobody has uncovered any evidence that it did.
- Michigan regulations require the challenger to not only prove probable cause, but also to file challenges county-by-county. Michigan is the closest margin state Stein says she wants to challenge. But even there, Trump’s win exceeds the largest margin ever overcome in a recount.
Wisconsin apparently has more permissive rules, so a recount may be possible there. But to switch the winner, Trump would have to lose 36 electoral votes to Clinton. Wisconsin only has 10 electoral votes.