Democrat Hillary Clinton won Florida, Ohio and North Carolina on Tuesday, completing her sweep of the South and halting Vermont Sen. Bernie Sanders' momentum in the industrial Midwest. Her strong showing makes her the party's undeniable frontrunner, though Sanders seems poised to pick up enough delegates to keep close.

Clinton has long had an advantage over Sanders in diverse states like Florida and North Carolina, but Sanders' shocking Michigan win last week had his supporters hoping that the race might have shifted. Clinton's victory in Ohio, though, proved she could carry the pivotal swing states in the nation's heartland.

"You voted for our tomorrow to be better than your yesterday. Tomorrow, when all of us do our part, and everyone has a chance to live up to his or her God-given potential," Clinton said at her rally in West Palm Beach, Fla. "Because that's how America can live up to its potential, too."

After a narrow victory in Iowa's caucuses and a resounding defeat in New Hampshire's primary, Clinton bounced back with resounding wins in South Carolina, Georgia, Texas and the rest of the region. Fueled by overwhelming support from Hispanics and minorities, she racked up a daunting lead in the race for delegates and "superdelegates" - the party elite who can pick whomever they want.

Yet Sanders, whose call for a "revolution" has enthralled young and liberal voters, has held his ground with victories in Maine, Kansas and Nebraska. And his stunning upset victory in Michigan, where Clinton long held an advantage in the polls, seemed to breathe new life into his campaign.

That momentum evaporated on Tuesday as Clinton surged across the board. In her victory speech, the former secretary of state cast herself as the candidate who could unite the liberal wing of the party with the more mainstream elements.

Voters in five states cast ballots on Elimination Tuesday, which is shaping up to be the most decisive day in the primary calendar. Florida, Ohio, Illinois, North Carolina and Missouri hold primaries, and hundreds of delegates are up for grabs. It's also the first time huge troves of delegates are at stake in winner-take-all Republicans contests.

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