There already was one New Yorker being prosecuted for voting twice isn't there?
I think that they got a couple in the last 2002 election.
Since posting my earlier reply, I have come up with a plan.
The conservatives in Floriduh need to come up with a pool of money and pay a bounty to anyone who can document a snowbirder who votes twice and is convicted of voter fraud.
Several thousand $'s of such reward money potential in each key Snowbird area might scare these old rats away.