By JULIE PACE and JILL COLVIN
WASHINGTON (AP) -- Republican Donald Trump and Democrat Hillary Clinton swept through the South on Super Tuesday, with the front-runners claiming victory in their parties' primaries in delegate-rich Georgia, Tennessee and Virginia. Clinton also carried Texas, the night's biggest prize.
On the Republican side, Ted Cruz won his home state of Texas, as well as neighboring Oklahoma. Democrat Bernie Sanders picked up a home-state win as well, in Vermont, and won in Oklahoma, too.
Still, the night belonged to Trump and Clinton, who turned the busiest day of the 2016 primaries into a showcase of their strength with a wide swath of American voters.
"What a Super Tuesday," Clinton exclaimed during a victory rally.
As Trump's victories piled up, he fired off "thank you" Twitter notes to the states that landed in his win column. The billionaire businessman scheduled a nighttime news conference at his swanky Mar-a-Lago resort in Florida, eschewing the traditional election night rally.
Cruz desperately needed a win in Texas in order to stay in the race, and was likely to keep campaigning as the only Republican who has been able to defeat Trump in any primary contest.
For Florida Sen. Marco Rubio, the night was turning into a disappointment. While a flood of Republican officeholders have rallied around him in recent days, his first victory remained elusive as results rolled in.
Still, Rubio, who has launched an aggressive campaign to stop Trump in recent days, vowed to keep up his efforts to "unmask the true nature of the front-runner in this race."
The Florida senator's long-shot White House hopes now rest with his home state, which votes on March 15. But he's expected to face fresh calls from Trump and others to drop out of the race before then.
"He has to get out," Trump told Fox News earlier in the day. "He hasn't won anything."
Super Tuesday marked the busiest day of the 2016 primaries, with the biggest single-day delegate haul up for grabs. Democrats voted in 11 states and American Samoa, with 865 delegates at stake. Republicans voted in 11 states, with 595 delegates.
Clinton also picked up wins in Alabama and Arkansas, while Trump carried the GOP contests in Alabama and Massachusetts.
Clinton steadied herself after an unexpectedly strong challenge from Sanders. The Vermont senator did carry his home state decisively, and told the crowd at a raucous victory party that he was "so proud to bring Vermont values all across this country."
Exit polls underscored Sanders' continued weakness with black voters, a core part of the Democratic constituency. Clinton led with African-Americans, as well as both men and women, in Georgia and Virginia, according to surveys conducted by Edison Research for The Associated Press and television networks.
Sanders continued to show strength with young voters, carrying the majority of those under the age of 30.
The contests come at a turbulent time for the GOP, given Trump's strengths in the face of opposition from many party leaders. Some in the party establishment fear the anti-Trump campaign has come too late.
Trump's wins in the South were a blow to Cruz, who once saw the region as his opportunity to stake a claim to the nomination.
Republicans spent months largely letting Trump go unchallenged, wrongly assuming that his populist appeal with voters would fizzle. Instead, he's appeared to only grow stronger, winning states and drawing broad support for some of his most controversial proposals.
In six of the states on Tuesday, large majorities of Republican voters said they supported a proposal to temporarily ban all non-citizen Muslims from entering the United States, an idea championed by Trump. Two-thirds of GOP voters in Texas, Virginia and Georgia, 7 in 10 in Tennessee, and nearly 8 in 10 in Alabama supported the proposal, according to the early exit polls.
Worries among Republicans appeared to grow after Trump briefly refused to disavow former Ku Klux Klan leader David Duke during a television interview. Trump later said he had not understood the interviewer who first raised the question about Duke, and he did repudiate him.
House Speaker Paul Ryan said Tuesday that anyone who wants to be the Republican presidential nominee must reject any racist group or individual.
States holding voting contests in both parties were 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.
Colvin reported from Palm Beach, Florida. AP writer Julie Bykowicz in Washington and Ken Thomas in Burlington, Vermont, contributed to this report.
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