Each party holding contests in 11 states. Democrats also vote in American Samoa.
Republicans will allocate 595 delegates from the results of Super Tuesday, nearly half of the 1,237 needed for the nomination.
Democrats will allocate 865, more than one-third of the necessary 2,383.
ABC News will be providing live coverage as the results come in. Amna Nawaz and Richard Bacon will anchor coverage with LZ Granderson, Rick Klein and other political voices and analysts beginning at 7:00 p.m. ET | 4:00 p.m. PT.
WATCH LIVE COVERAGE FROM ABC News
Strait Talk with Matt Dowd and LZ Granderson (Below at 7:15 p.m. ET | 4:15 p.m. PT)
You can watch more ABC News live streams from at abcnews.com/live.
Both parties are holding contests Tuesday in these states: Alabama, Arkansas, Georgia, Massachusetts, Minnesota, Oklahoma, Tennessee, Texas, Vermont and Virginia.
Republicans also vote in Alaska and Democrats in Colorado. Democrats also have a contest in American Samoa and for Democrats Abroad.
In the 12 states holding contests, polls close at 7 p.m. EST in three (Virginia, Georgia and Vermont), and at 8 p.m. EST in four more (Oklahoma, Alabama, Tennessee and Massachusetts). The rest, Eastern time: 8:30 p.m. in Arkansas, 9 p.m. in Texas, Colorado and Minnesota; and 1 a.m. in Alaska.
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