9:14 p.m. ET CBS News projects Sanders has won Indiana's primary in a major upset.
7:45 p.m. ET Sanders spoke to a rally of his supporters in Louisville, Kentucky on Tuesday night.
He gave his usual stump speech about income inequality, college debt and Social Security benefits.
"As of today, we have now won 17 primaries and caucuses. We have received some nine million votes. When we started this campaign, we were 60 points behind Secretary Clinton in national polls," he said. "We end up winning the vote of people 45 years of age or younger. That is important because it tells me that the ideas that we are fighting for are the ideas for the future of America and the future of the Democratic Party."
7:22 p.m. ET Sanders is getting the support of both men and women while Clinton continues to perform well with black voters who make up 17 percent of Democratic primary voters in Indiana. About three-quarters back Clinton. Sanders wins among the three-quarters of white Democratic Indiana primary voters.
Sanders continues to run strong with younger voters -- 72 percent of 17 to 29 year olds support him. Clinton performs well among older voters -- 60 percent of people over the age of 65.
More Indiana Democratic primary voters think Clinton, 50 percent, would have a better chance to defeat Trump than Sanders, 47 percent.
More voters, 76 percent, said they see Clinton's proposed policies as more realistic than the 67 percent who said the same about Sanders' proposed policies.
Most Clinton and Sanders supporters say they would probably or definitely vote for either candidate if they became the nominee. Thirty percent of Sanders' primary voters currently say they would not back Clinton in November, and 19 percent of Clinton supporters say they wouldn't vote for Sanders.
7:00 p.m. ET Polls have officially closed in Indiana.
6:14 p.m. ET Caring about people and the candidates' honesty are the top qualities that mattered most to Indiana Democratic primary voters.
While Republicans say the campaign has divided their party, about three-quarters of Democratic primary voters in Indiana say the campaign has energized their party.
Nearly nine in ten Indiana Democratic primary voters say the country is ready to elect a woman president.
5:00 p.m. ET The first set of polling places in Indiana -- those in the Central time zone -- close in the next hour, at 6 p.m., ET, while the other parts of the state, on Eastern time, polls are expected to close in two hours, at 7 p.m.
Preliminary exit polls show a plurality of voters in the Democratic race named the economy and jobs as the most important issue for them in Indiana. Nearly two-thirds said Wall Street hurts the economy while just under a third said it helps it.
Twenty-seven percent of Democratic primary voters said Hillary Clinton has attacked Bernie Sanders unfairly while 19 percent said the same about Sanders attacking Clinton.
Exit polls also show that nearly three-quarters expect Clinton to be the Democratic nominee while only 27 percent said the same about Sanders' chances. Half of Democratic voters in Indiana want to see the next president continue President Obama's policies and just over a third want more liberal policies.
On the Democratic side, Indiana allocates 92 delegates and they are awarded proportionally between the candidates that get at least 15 percent of the statewide vote.
Because Indiana operates under an open primary system, any registered voter can cast a ballot in either the Democratic or Republican race regardless of party affiliation. This means independents can participate.
According to CBS News' latest count, Clinton has 2,165 delegates, including superdelegates and Sanders has 1,346.
CBS News polling analyst Melissa Herrmann contributed to this report.
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