Yeah, thats one of the dumbest things I ever heard of, democrats allowed to vote in a republican primary. Another dumb thing is this delegate awarding mess. Some states giving all and some not.
Happens all the time most states don't know if one is DEM or PUB when they vote in primaries. Since the President has noone running against him thy skew the nomination in their state for the candidate that can't defeat their candidate.
American politics. To bad they have forgotten that we are a Republic not a Democracy.