Hillary Clinton has secured the Democratic Party's 2016 nomination for the White House, becoming the first woman in US history to head the ticket of a major party.

Delegates from South Dakota gave Clinton 15 votes, ensuring that she had more than the 2383 votes needed to win the nomination during a state-by-state roll call at the Democratic convention in Philadelphia on Tuesday.

After a tough battle with Democratic rival US Senator Bernie Sanders, Clinton is now the party's standard-bearer against Republican nominee Donald Trump in the November 8 election.

Delegates chanted "Hillary, Hillary" as US Senator Barbara Mikulski of Maryland formally put forward Clinton's name for the alphabetical roll-call vote.

"Yes, we do break barriers, I broke a barrier when I became the first Democratic woman elected to the Senate in her own right," Mikulski said.

"So it is with a full heart that I'm here today to nominate Hillary Clinton to be the first woman president," Mikulski said.

Sanders has endorsed Clinton, a former first lady, US senator and secretary of state, but some of his supporters protested in Philadelphia against the party leadership's apparent backing of her during the bitter Democratic primary fight.

Supporters of Clinton say her Washington credentials show she has the experience needed for the White House during troubled times as the US tries to speed up its economic recovery and faces security challenges abroad.

Detractors view her as too cosy with the establishment and say she carries political baggage dating back to the start of her husband President Bill Clinton's first White House term in the 1990s.