Democrat Hillary Clinton and Republican Donald Trump were the big winners on the most important day of voting in the nominating race for the United States presidential election, proving themselves the undisputed front-runners of their parties on Tuesday (March 1).

Mrs Clinton, the former secretary of state, swept seven of the 11 states and one territory that went to the polls on Super Tuesday to pick their Democratic nominee. She secured victories in Alabama, Arkansas, Georgia, Massachusetts, Tennessee, Texas and Virginia, as well as the US territory of Samoa.

Mr Trump also clinched seven victories - the competitive swing state of Virginia, Arkansas, Alabama, Georgia, Massachusetts, Vermont and Tennessee - out of 11 states, adding to a sense of momentum he had built last month by winning three of the first four contests.

Mr Trump's rival Ted Cruz, a senator from Texas, won his home state and neighbouring Oklahoma. He also won the Republican caucuses in Alaska by a slim margin over Mr Trump, bolstering his argument that he had the best chance to spoil Mr Trump's chances.

Senator Marco Rubio of Florida, favourite of the Republican establishment, took Minnesota, in his first victory.

Mrs Clinton's rival Bernie Sanders, a senator from Vermont, won his home state along with Colorado, Minnesota and Oklahoma.

In her victory speech, Mrs Clinton said she would not take votes for granted.

"We are going to work with every vote and we will need all of you volunteering, contributing, talking to your friends and neighbours, because this country belongs to all of us," she said in Florida, the venue of the next primary on March 15.

Slighting Mr Trump a couple of times during her speech, Mrs Clinton said: "I believe what we need in America today is more love and kindness, because you know what, it works, instead of building walls we are going to break down barriers and build ladders of opportunity and empowerment so every American live up to his or her potential."

Mr Trump has worried many in the Republican establishment with proposals such as building a wall along the US southern border with Mexico, deporting 11 million illegal immigrants and slapping a temporary ban on Muslims entering the country.

The Republican front runner hit back at Mrs Clinton in his speech: "She wants to make America whole again...What's that all about? Making America great again is better than making America whole again."

At a news conference in a chandeliered ballroom at his seaside Mar-a-Lago resort in Palm Beach, Florida, Mr Trump, who has never held public office, also dismissed furious criticism aimed at him by establishment Republicans.

Mr Trump declared he had expanded the party by drawing in disaffected blue-collar Democrats who like his tough-on-trade rhetoric. "I am a unifier," he said. "I would love to see the Republican Party and everybody get together and unify, and when we unify, there's nobody that's going to beat us." The rivals of both Mr Trump and Mr Clinton aim to knock them off their pedestals this month in contests in Michigan, Florida and Illinois.

Expected home wins went to Republican Texas senator Ted Cruz and Democrat Vermont Senator Bernie Sanders, whose campaigns would have been dealt huge blows if they failed to win those states.

Both are also projected to win Oklahoma - a significant win that would keep their campaigns alive as they move to the next round of primaries on March 15.

"At the end of tonight, 15 states will have voted, 35 states will remain," said Mr Sanders. "Let me assure you that we are going to take our fight for economic justice, for social justice, for environmental sanity for a world of peace to every one of those states."

Mr Sanders told Vermont residents that he is proud to "bring Vermont values all across the country".

"In Vermont, billionaires do not buy town meetings, and in America we are going to end a corrupt campaign finance system," said Mr Sanders, once again pounding away at one of his key election issues.

He also assured supporters that Super Tuesday is but one part of the race to the White House.

Super Tuesday was the biggest single day of state-by-state contests to select party nominees for the Nov 8 election to succeed Democratic President Barack Obama. Voting stretched from eastern states to Texas and Minnesota.