11:29 p.m. CBS News projects Hillary Clinton as the winner of the Illinois Primary.
9:04 p.m. Following her third victory of the night, in Ohio, Clinton spoke to supporters in West Palm Beach, Fla.
"We are moving closer to securing the Democratic Party nomination and winning this election in November," she said.
The candidate also referenced Sanders, and thanked him for a hard-fought campaign: "I want to congratulate Sen. Sanders for the vigorous campaign he's waging," she said.
8:45 p.m. Hillary Clinton is projected to win the Ohio Democratic primary, CBS News projects.
8:24 p.m. As the results come in from Illinois, here's what the exit polls say about the Clinton-Sanders race there:
Women are breaking for Clinton (54 percent), while men are going for Sanders (56 percent). Just over a quarter of voters (27 percent) are African American, Clinton is getting about 69 percent of them, while 30 percent are for Sanders -- far higher than his margins in most other states that have voted thus far. Sanders currently has the backing of 60 percent of white voters.
Clinton has a slight edge as to who would make the best commander-in-chief, with 51 percent of Illinois primary voters naming her. The majority (64 percent) say Clinton would have the better chance in defeating Donald Trump in November. Still, more Illinois primary voters say Sanders (55 percent) inspires them about the future than Clinton (44 percent).
Of those who think that trade with other countries will take away U.S. jobs (46 percent), the majority of them, 59 percent, support Sanders. The Vermont senator has criticized Clinton over her support for trade deals like the North American Free Trade Agreement.
8:19 p.m. CBS News projects Hillary Clinton wins in North Carolina.
8:07 p.m. With Clinton picking up her first victory of the night in Florida, here's what the exit polls say about how she did it:
Although Clinton continues to carry her strong support among older voters, with 72 percent of those over 45 voting for her, Sanders does not have the stronger support among young voters in Florida. Among the Florida primary voters, the support among the 18- to 44-year-olds is much closer, with 52 percent voting for Sanders and 48 percent for Clinton.
Of the 20 percent of Florida primary voters who are Hispanic, the majority (69 percent) are backing Clinton. Of the 45 percent of Florida primary voters who think that race relations have gotten worse over the past few years, the majority support Clinton (61 percent).
More than half of voters (54 percent) want to continue Obama's policies, and 75 percent of those voters chose Clinton.
The majority of Florida primary voters see Clinton's policies as realistic (78 percent), while less than half think Sanders' policies are realistic. Almost three-quarters feel that Clinton would have the better chance to defeat Donald Trump in November.
Of the 17 percent of voters who made their decision in the last week, 61 percent broke for Clinton.
8:00 p.m. CBS News projects Hillary Clinton wins in Florida.
CBS News reports that the Democratic race is a toss-up between Clinton and Sanders in Illinois and Missouri.
7:53 p.m. And we've got exit polling data out of Ohio, too. Here are the highlights:
Sixty-two percent of Democratic voters believe that Clinton has the better chance to defeat Donald Trump in November. The majority of Ohio Democratic primary voters (53 percent) believe Clinton would make the best commander-in-chief.
Although more primary voters continue to see Sanders (80 percent) as honest and trustworthy than Clinton (59 percent); more thought that Clinton's policies are realistic (76 percent) than Sanders' (60 percent).
The Ohio trends in age are similar to North Carolina: Clinton continues to perform well with older voters, with 65 percent of those over 45 voting for Clinton, while Sanders takes 70 percent of the 18- to 44-year-old Ohio primary voters.
Of those identifying as independent, 70 percent support Sanders. The majority (63 percent) of non-white voters support Clinton.
Thirty-one percent of Ohio Democratic voters feel Clinton's views on business are too pro-business, while 27 percent feel that Sanders is too anti-business. Of the voters who decided in the last week, 60 percent are backing Sanders.
7:40 p.m. Now that the polls are closed in North Carolina, here's some interesting stats from the exit polling there:
Clinton continues to get strong support among older voters, with 63 percent of those over 45 voting for her. Sanders, as usual, performs well with younger voters, getting 59 percent of the 17-44 year-old North Carolina primary voters. Almost 30 percent of North Carolina primary voters are African American, and 80 percent of those voters support Clinton (compared to 18 percent support who Sanders).
Among self-identified independent voters, 60 percent support Sanders.
The majority of North Carolina Democratic voters (59 percent) believe that race relations have gotten worse in this country in the last few years. Of those, support is split with 49 percent supporting Clinton and 46 percent supporting Sanders.
Only 58 percent of North Carolina primary voters think that Clinton is honest and trustworthy, while 82 percent believe that Sanders is honest and trustworthy. Sanders's policies are thought to be realistic by just over half (54 percent) of North Carolina primary voters, whereas Clinton's policies are seen as realistic by 79 percent of voters.
Over half (52 percent) of North Carolina primary voters who made their decision within the last week support Sanders.
Clinton is seen as the candidate who would make the best commander in chief by 56 percent of North Carolina primary voters. When asked who would have the better chance to defeat Donald Trump in November, 66 percent say Clinton.
7:30 p.m. CBS News reports that Hillary Clinton leads Bernie Sanders in Ohio and North Carolina.
6:04 p.m. With just under an hour until the first polls begin to close in Florida, here's a reminder of what's at stake delegate-wise tonight:
5:56 p.m. Here are some more facts from the Democratic exit polls so far:
The wide majority of Democratic primary voters said they decided who to vote for before a month ago: the percentage ranges from 57 percent in Illinois to 69 percent in Florida. About a quarter of Democratic primary voters made their decision in the last week: in Florida, it was 16 percent; in Illinois, 24 percent; in Missouri, 22 percent; in North Carolina, 25 percent; and in Ohio, 23 percent.
The majority of Democratic primary voters say they're either "somewhat" or "very" worried about the direction of the nation's economy in the next few years: in Florida, that figure is 66 percent, compared with 86 percent in Illinois, 81 percent in Missouri, 72 percent in North Carolina and 75 percent in Ohio. About three in 10 Democratic voters say they are "very worried" about the direction of the nation's economy in the next few years.
And in the wake of conversations about police brutality and violence against African Americans, the majority of primary voters in all states thought race relations in this country have gotten worse. That figure is highest in North Carolina (60 percent) and Missouri (59 percent); it's lowest in Florida (45 percent).
5:15 p.m. The first round of early exit polling is in from the five states that vote tonight. Here are some interesting statistics:
Across the board, Democrats named the economy and jobs as their most important issue. As for candidate qualities, the exit polls show a mixed result: in Illinois and Missouri, a candidate who is "honest and trustworthy" was deemed most important, while in North Carolina and Ohio it was one who "cares about people." In Florida, the top candidate quality was someone who has the "right experience."
And a majority of Democrats in each state except Ohio said they want to see the next president continue President Obama's policies, rather than pursuing policies that are more or less liberal. (In Ohio, 48 percent said they want someone to continue Obama's policies, while 34 percent wanted more liberal policies and 12 percent wanted less liberal policies.)
5 p.m. It's primary night again in America, with five states holding nominating contests Tuesday. Voters are heading to the polls in Ohio, Florida, North Carolina, Illinois and Missouri today.
The Democratic candidates are former secretary of State Hillary Clinton and Vermont Sen. Bernie Sanders.
The biggest prizes on the map Tuesday are Ohio and Florida, both general-election swing states. Though Clinton appears to have a solid lead in Florida, things look tighter in Ohio--and after Sanders's upset victory in Michigan next week, observers wonder whether he'll be able to pull off any similar surprises this week.
For Democrats, 691 delegates total are at stake across the five states. According to CBS News' latest count, Clinton leads with 1,222 delegates to Sanders's 565. A candidate needs 2,383 delegates to win the nomination.
Most of Florida closes at 7 p.m. ET, but the panhandle in the western part of the state is in the central time zone -- that part closes at 8 p.m. ET. Polls close in Ohio and North Carolina at 7:30 p.m. ET and in Missouri and Illinois at 8 p.m. ET.
CBS News Poll Analyst and SSRS President Melissa Herrmann contributed to this story.
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