Ahh Fred Phelps, a man the democrats wont admit is theres.
To be fair, Phelps is no more a Democrat than he is a Christian. Calling himself one (and running as one) doesn't make it so. If tomorrow he ran for office as a Republican I would expect the Republican party to distance themselves from him as well.
In this country anyone can run for office under whichever party they choose. Getting support from that party is a whole different matter.
In all fairness I don't see the GOP bragging about David Duke.