Hillary secures enough delegates for the Democratic nomination.

Reuters - Democratic presidential candidate Hillary Clinton has reached the number of delegates needed to win the Democratic Party's nomination to run for president of the United States, according to polls by two US media outlets, although she and her rival Bernie Sanders are still competing in primaries in six states on Tuesday.

Former New York senator and former Secretary of State, Hillary Clinton would have been the first woman in the country's history to run as a presidential candidate for a major political party. But Sanders vowed to continue the fight, in what has been a long and increasingly belligerent race through state elections.

Sanders, a Vermont senator who identifies as a democratic socialist, has thrilled large audiences at rallies held in parks and stadiums, electrifying young voters with his commitment to tackling economic inequality.

But Hillary continued to gain ground on Sanders, particularly among older voters with deeper ties to the Democrats. Her less ambitious promises focus on improving upon the policies of her party colleague and former boss, President Barack Obama.

After the Associated Press news agency and the NBC television network reported on Monday night that Hillary Clinton had secured the required number of delegates for the Democratic nomination, a spokesman for the Sanders campaign criticized what he called the media's "rush to judgment."

According to the rules of the Democratic National Committee (DNC), the majority of delegates to the party convention from July 25 to 28 are granted by popular vote in state-by-state elections.

But the count also includes "superdelegates"—party leaders and elected senators, members of Congress, and governors—who can vote as they see fit.

For this reason, the DNC echoed Sanders' camp, saying that superdelegates should not be taken into account until they have actually voted at the Philadelphia convention. This, however, did not stop the news coverage.

AP and NBC reported that Hillary Clinton secured the 2.383 delegates she needs to be officially nominated as the likely Democratic nominee thanks to a decisive victory over the weekend in Puerto Rico, a U.S. territory, and a wave of last-minute endorsements from superdelegates.

"According to the news, we are on the verge of a historic, unprecedented moment," Hillary said during a rally in Long Beach, California, shortly after the AP announcement.