Hillary Clinton defeated Bernie Sanders in a landslide in Saturday's Democratic primary in South Carolina, projections showed, seizing momentum ahead of the most important day of the nomination race: next week's "Super Tuesday" showdown.
Four weeks into the White House primaries, the former secretary of state earned a decisive win in the first southern state to vote for a 2016 Democratic nominee, before the race broadens to 11 contests across the country.
"Tomorrow this campaign goes national," Clinton said to a loud roar as she thanked supporters in Columbia, South Carolina.
"We are going to compete for every vote in every state. We are not taking anything, and we are not taking anyone, for granted."
US networks called the race for Clinton moments after polls closed in the Palmetto State, where the majority of Democratic voters are African-American, a voting bloc that she and her husband, former president Bill Clinton, have successfully courted for decades.
Clinton also looked beyond her battle with Sanders, tweaking the man many now see as the likely Republican nominee: Donald Trump, whose campaign slogan is "Make America Great Again."
"Despite what you hear, we don't need to make America great again. America has never stopped being great," she said.
"But we do need to make America whole again," she added, laying out an argument against the divisive rhetoric favored by Trump, who has antagonized immigrants, Muslims and campaign rivals.
"Instead of building walls, we need to tear down barriers," Clinton said.
"I know it sometimes seems a little odd for someone running for president these days and in this time to say we need more love and kindness in America," she added. "But I am telling you from the bottom of my heart, we do."
With nearly 79 per cent of precincts reporting, Clinton stood at 73.6 per cent compared to 25.8 per cent for Sanders.
The victory marks an impressive moment of redemption for Clinton who in 2008 lost badly in the state to Barack Obama - his win here serving as a turning point for his ultimately victorious campaign.
Exit polls in South Carolina showed African-American voters -- who represented 61 per cent of all Democratic voters in the primary -- backed Clinton by a stunning 87 per cent, against 13 percent for Sanders.
Saturday's result was a foregone conclusion of sorts, with Sanders bolting early Saturday for Texas and then Minnesota, two states in play next Tuesday when the Vermont senator needs to keep his head above water if he wants to challenge Clinton deeper into the nomination race.
Sanders swiftly offered his congratulations, but also insisted he was in it for the long haul.
"Let me be clear on one thing tonight. This campaign is just beginning," he said in a statement.
"We won a decisive victory in New Hampshire. She won a decisive victory in South Carolina. Now it's on to Super Tuesday."
'Con artist' as GOP frontrunner?
As the Democrats voted, the Republican race churned on with frontrunner Donald Trump trading barbs with rival Marco Rubio, who in recent days has launched a fierce assault on the billionaire real estate mogul.
"I want to save the (Republican) party from a con artist," Rubio, seen by many as the man best-positioned to topple Trump, said at a stop in Kennesaw, Georgia.
Rubio accosted Trump for "flying around on hair force one," and having "the worst spray tan in America."
Trump pushed back during a speech in Arkansas, one of the dozen states voting Tuesday.
"I watched this lightweight Rubio, total lightweight," Trump sneered. "I'm a con man, right? I built a great business!"
Among Democrats, Clinton leads in the national delegate count at this early stage, having now won three of the first four nomination contests - in Iowa, narrowly, then Nevada and South Carolina.
Gloria Major, a grandmother and campaign volunteer who supported Clinton in 2008, was among the ecstatic crowd listening to her victory speech in South Carolina.
"She has been in battles, she is one woman that can lead this country," Major told AFP. "For years she has had our best interest at heart."
Only three percent of delegates for July's nominating convention in Philadelphia will have been awarded by Saturday's end.
But the 11 states that hold Democratic nominating contests next Tuesday will send a whopping 18 per cent of the delegates to Philadelphia.
Clinton is ahead in most, but Sanders has the edge in Massachusetts and his home turf of Vermont.
Sanders, who calls himself a democratic socialist, told a crowd of some 10,000 people earlier in Texas that he has been this election's comeback kid.
Looking beyond next Tuesday, he is also focusing on states like Ohio and Minnesota that vote later in the crucial month of March, during which a whopping 45 per cent of all delegates to the nominating convention are up for grabs.