The voter rolls should be purged after every national election. With new technology, you can vote from your iPhone and it will be more secure than what is going on now. And it is simple.
There is a national database with SS numbers. On election day only, you log into your phone and you vote. Your SS number is your voter ID. Once you vote, your name is digitally crossed off the list so you cannot vote again. No need for polls, poll workers or machines. The copy of the database is temporary and after the election it is deleted.
And the best part is, this system can be implemented in 3-6 months. Build the mobile app and voters download the app. The sign in is SS number plus a user created temporary password which has to be validated by text to ensure the user is real. Cheating has just been eliminated and with the temporary database, since it will be read only until the vote is case, it cannot be hacked.
SSNs are a good cross-check but remember, we had a man win the Presidency while holding a “churned” (stolen) SSN.