WASHINGTON (Reuters) - The race for the Democratic nomination is effectively down to a tight two-way race after almost a third of U.S. states cast ballots on Super Tuesday, with front-runners Joe Biden and Bernie Sanders drawing support from sharply divergent groups.

Poll workers walk inside a polling station inside Forest Hill Clubhouse during the presidential primary election on Super Tuesday in San Francisco, California, U.S. March 3, 2020. REUTERS/Stephen Lam

According to Edison Research exit polling, African Americans, older people and college graduates largely supported Biden in the 14 nominating contests, helping him win at least eight states.

Latinos, millennials and white men largely backed Sanders, helping him to likely wins in the western states of Colorado and delegate-rich California.

Biden and Sanders also split the vote in Texas, as the candidates’ demographic advantages essentially canceled each other out.

(Get all the Super Tuesday action: here)

Edison, which compiles voter polls and live election results for media organizations including ABC News, CBS News, CNN, NBC News and Reuters, also found that as many as half of Super Tuesday voters made up their minds in the last few days. The lion’s share of those late deciders backed Biden.

The results reflected how Biden, who recovered from poor showings in the first two nominating contests, was benefiting from his dominant win in Saturday’s South Carolina primary and endorsements he picked up from Senator Amy Klobuchar and Pete Buttigieg, a former South Bend, Indiana, mayor, two fellow moderates who dropped out of the race in recent days.

The polling found that late deciders ranged from five out of 10 voters in Virginia, Oklahoma, Minnesota and Massachusetts, to two out of 10 in Texas and California.

In almost every case, those late deciders broke at least 2-to-1 in favor of Biden, a former vice president, over Sanders, a senator and self-described democratic socialist who leads in national opinion polls in the Democratic race to find a challenger to Republican President Donald Trump in November’s election.

Slideshow ( 6 images )

In the case of Klobuchar’s home state of Minnesota, a little more than half of voters said they made up their minds in the “last few days,” and about 49% of them went for Biden, while 21%supported Sanders.

Here are other highlights from the poll, which was based on interviews with people who voted on Tuesday in 12 of the 14 Super Tuesday states. The proportions may change as more polling is conducted and votes are tallied:

** A large majority of Democratic primary voters said they would support the party’s nominee regardless of who it is, including 86% of primary voters in California and Texas, and eight of 10 in Virginia, Massachusetts in North Carolina.

** Voters in five of the bigger states holding primaries on Tuesday said the coronavirus outbreak was a factor in their decision. The political and economic crisis over the outbreak, which has infected some 90,000 people worldwide and killed more than 3,000, is escalating.

** Less than two of 10 voters in the Super Tuesday primaries are first-time primary voters.

** In California, Biden won the largest share of African Americans at 38%, while Sanders won 55% of Latinos.

** In Texas, Biden won 60% of black voters, while Sanders won the largest share of Hispanics at 45%.

** Super Tuesday voters largely named healthcare as their top issue, and half or more supported a government-run single-payer system championed by Sanders.

** At least seven out of 10 voters in California, Texas, Virginia, North Carolina and Tennessee said the recent coronavirus was a factor in their decision. Those were the only states in which the question was put to voters.

** Edison polled voters in 12 of the 14 states holding primaries on Tuesday. It did not conduct exit polls in Arkansas and Utah.