Cursive or print?
If you have already written letters in cursive, this is fine. You should not redo them.
Many young voters did not learn cursive in school, so printing your handwritten message is safer than writing in cursive because we do have young voters on our mailing lists. Also, please print the addresses on the envelopes. We learned from a volunteer, who is also a mail carrier, that this is helpful when it comes time to deliver your letters to your voters, and printing addresses in all caps is USPS's preference.