Hillary Clinton makes history as she is named presumptive Democratic presidential nominee

The Associated Press reported that she had surpassed the total of 2,383 delegates needed to secure the nomination

Hillary Clinton campaigned on Monday, which is set to vote on Tuesday with five other states (GETTY)

Hillary Clinton is to become the first female presidential candidate of a major US political party, after surpassing the number of delegates necessary to secure the Democratic nomination, the Associated Press reported on Monday.

The news agency keeps what is considered the authoritative tally of electoral delegates. It counted pledged delegates won by Ms Clinton in primaries and caucuses, and surveyed Democratic super-delegates – the party grandees who also cast a vote – to find that the former Secretary of State now has the support of at least 2,383 delegates in total, the majority required to claim the nomination.

Ms Clinton was likely pushed over the threshold by winning the Puerto Rico primary on Sunday evening, and, as the presumptive nominee, is now expected to formally accept the nomination at the Democratic convention in Philadelphia in July before facing Republican Donald Trump in November's general election. The news comes the day before the last major day of primary season, with votes being held in New Jersey, California and four other states on Tuesday.

Ms Clinton's campaign tweeted on Monday evening that she was "flattered" by the Associated Press report, but said she was focussed on Tuesday's primaries, adding: "We are on the brink of a historic moment, but we still have work to do."

Ms Clinton’s challenger, progressive Vermont Senator Bernie Sanders, has thrown his remaining resources into contesting California, where the two are neck and neck in polls. He has insisted Ms Clinton cannot reach the necessary delegate count without super-delegates, who do not cast their votes until the convention, and has vowed to try to convert them before then.

A spokesman for Mr Sanders said last night: "Secretary Clinton does not have and will not have the requisite number of pledged delegates to secure the nomination. She will be dependent on superdelegates who do not vote until July 25 and who can change their minds between now and then."

Traditionally, super-delegates have backed the candidate who wins the popular vote and thus secures the greatest number of pledged delegates. Ms Clinton has so far won several more states than Mr Sanders, close to 300 more pledged delegates and some three million more individual votes.