US senator Bernie Sanders has announced that he will make a second attempt at winning the Democratic Party presidential nomination next year.
Sanders, who is an independent who caucuses with the Democrats, became a political favourite when he lost his bid for the party's nomination in 2016 to former first lady Hillary Clinton.
Making the announcement over public radio in his constituent state of Vermont, the 77-year-old senator said: "We began the political revolution in the 2016 campaign, and now it's time to move that revolution forward."
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Early polls have suggested he is far ahead of other candidates who have announced or are suspected to bid for the Democratic spot, according to the BBC.
Sanders is an outspoken critic of US President Donald Trump, calling him "an embarrassment to our country", "a pathological liar" and "a racist" in his announcement today.
The senator previously won support from Democrats over his calls for a universal healthcare system provided by the state, as well as a $15 minimum wage and free college tuition.
He was particularly popular among young voters, who racked up millions of dollars in small donations to his campaign in 2016.
Other candidates who have announced bids so far include Elizabeth Warren, Kamala Harris, Cory Booker, Amy Klobuchar and Julian Castro. Next year's primary will be the first time in US history that more than one woman has contested for the Democratic nomination.
Sanders was first elected to the US House in 1990, and won a seat in the Senate in 2007. Prior to his last presidential bid, he was best known for speaking for eight and a half hours in order to prevent the extension of tax policies in 2010 which he believed worsened the US' income gap.