A ballot measure to enshrine abortion rights in the Arizona constitution will be on the November ballot. Arizona polls (and past abortion ballot measures) suggest it should pass.
Conventional wisdom is that it will help turnout, but there is mixed evidence in that regard. Likewise plenty of Republicans voted for abortion ballot measures that otherwise voted for Republicans in other races.
Probably the strongest argument is they allow Democrats on the ballot to campaign on abortion and put the Republicans in a bind on the issue.
Likewise for ballot measures on marijuana/other drugs this cycle.