Democratic presidential candidates former Vice President Joe Biden and Sen. Bernie Sanders (I-VT) share a moment during the Democratic presidential primary debate in the Sullivan Arena at St. Anselm College on February 07, 2020 in Manchester, New Hampshire.

The graphics below show the delegates up for grabs in each state, along with key characteristics including race and health-care coverage.

Here are the states voting Tuesday, in alphabetical order. Polls started opening as early as 6 a.m.:

Fourteen states and American Samoa hold presidential primaries on Super Tuesday . The contests will award 1,344 national pledged delegates, more than a third of the total available in the 2020 Democratic race.

If Democrats are hurtling toward a brawl between Bernie Sanders and Joe Biden for their presidential nomination, Tuesday will help to set them on that path.

After jumping out to an early delegate lead, the independent Sen. Sanders of Vermont hopes to pull in enough delegates to propel him to the majority needed to snag the nomination. A big win in California, a 415-delegate jackpot where Sanders has comfortably led recent polls, would help to create some distance from Biden.

Biden hopes a few recent breaks will help him keep pace with Sanders. A huge win in Saturday's South Carolina primary brought him to 53 total pledged delegates, only seven short of Sanders. He appears competitive in Texas, which awards the second most delegates on Tuesday with 228, along with North Carolina and other Southern states.

By cutting into Sanders' margins in key states, Biden could improve the odds that no candidate heads to the Democratic National Convention in July with a majority of delegates. He got a boost when former South Bend, Indiana, Mayor Pete Buttigieg and Sen. Amy Klobuchar of Minnesota dropped out of the 2020 race in the last two days and endorsed him — moves that could consolidate more of the votes for a candidate other than Sanders.

The Vermont senator brushed off the endorsements Monday night. He told CNN he has fought the "establishment," and it's "no surprise they do not want me to become president."

Another rival to Sanders and Biden will enter the fray Tuesday. Former New York Mayor Mike Bloomberg, propelled by more than $500 million in personal spending, will appear on ballots for the first time.

The primaries will test his strategy of an ad bombardment across the country, particularly focused on Southern states. While he may lop off chunks of Biden's support, Bloomberg may not actually win any states.

Sen. Elizabeth Warren of Massachusetts also hopes to stack up delegates across the states, though she also may have a tough time prevailing in any individual states. She is even locked in a close race with Sanders in her home state, which votes Tuesday.

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