Five states are holding primaries Tuesday. The poll closing times are listed in the table below, along with the number of congressional districts in the state - all are up for election in November - and whether there is a Senate and/or gubernatorial election in 2018.

If you live in one of these states, click or tap the name to find your polling location.

¹ All times Eastern
² Percentage must be exceeded to avoid runoff; date of runoff election
³ There is a lot of local flexibility in poll closing times. This is the latest time for most locations.  If you are in North Dakota, check here for your polling place and hours.

Maine: Ranked-Choice Voting

Tuesday will see voters in Maine becoming the first in the nation to use ranked-choice voting (RCV) for statewide and congressional elections. It will apply to primary races with three or more candidates on the ballot. In those cases, voters will be able to rank as many of the candidates as they want in order of preference. If no candidate receives a majority of first-place votes, the candidate who receives the fewest of these is eliminated. The ballots that chose the now-eliminated candidate first are recounted, with each voter's second choice being added to the first-round totals. If this puts someone over 50%, we have a winner. If not, there are additional rounds of allocation until one candidate achieves a majority of the votes counted in that round.

For those interested, here's a painfully long video explaining the process: 

Whether this is the only Maine election to be conducted by RCV will also be decided on Tuesday (but not by RCV).