Virtually every state that uses machines prints out a paper ballot to be signed by the voter.
That's why ALL the swing states had long hand recounts of paper ballots even if they were using machines and machine counters.
States that use machines without (all or some) paper ballots:
KS
KY
LA
IN
MS
NJ
OK (disabled only)
TN
TX
Like I said, no swing states and ALL GQP controlled. Correction: NJ also uses some machines without paper ballot.
Every other state has a paper trail for every vote.
Ballotpedia: The Encyclopedia of American Politics
ballotpedia.org