I don't think you have to be registered to either party unless you participate in one of those political party activities (ie. caucus, party meetings, etc.).
When you register to vote, I -think- you just fill out the card and submit it. From then on you can vote... and get called by the courts to be in a jury.
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I USED TO HAVE an 85 Camaro 305 4bbl, 90 Firebird V6, 97 Firebird V6 (10 speakers!). Despite the two family vehicles, 3 kids, wife and mortgage, I can finally realize the dream - 88 TA almost all stock... for now.
http://www.cardomain.com/id/untameddave
Wanted this -

, but ended up with this -

for free. Can't argue with free.