If you are registered to vote in New York, you must be a registered Republican by 10/9/15 in order to vote for Rand in New York's 4/19/16 primary.

You can check your party enrollment here:

If you are not registered Republican, you can register online here:

The 10/9/15 deadline only applies to those who are already registered to vote. If you need to register to vote for the first time in New York, you have until 3/25/16.