Some googling from TNC on Ron Paul and the MLK holiday:
I'm sorry to report that one of those Nay votes, as you can see here, was cast by one Ronald Paul. I'm sorry to further report that Paul again voted no on the 1983 bill that passed.
There's this piece of evidence that seems to vindicate Paul. But it's merely about when to recognize the holiday, not whether to, so far as I can tell.
The Dish 