BETO O’ROURKE, the popular former congressman who rose to political stardom last year, has formally announced that he’s running for president of the United States.

The 46-year-old ended months of speculation by finally revealing that he will seek the 2020 Democratic presidential nomination today.

Until he challenged Republican Senator Ted Cruz last year, O’Rourke was little known outside his hometown of El Paso, Texas. But the former punk rocker became a sensation by running a social media savvy campaign that used grassroots organising to mobilise young voters and minorities.

He got within 3 percentage points of upsetting Cruz in the nation’s staunchest Republican state. Crucially for the presidential race, he also shattered national fundraising records in the process.

Now O’Rourke must prove whether the energy he brought to the Texas campaign will resonate on the national stage. Despite the enthusiasm associated with his candidacy, the former three-term congressman has little track record in domestic or foreign policy.

He’s also entering a field that has been celebrated for its diverse roster of women and people and colour. There are now 15 confirmed candidates for the Democratic nomination and another handful who are said to be considering a bid.

“This is going to be a positive campaign that seeks to bring out the very best from every single one of us, that seeks to unite a very divided country,” O’Rourke said in a video announcement with his wife on a couch. “We saw the power of this in Texas.”

I’m going to travel this country and listen to those I seek to serve” and then will return to El Paso on March 30 for a campaign kickoff. He invites would-be supporters “to the greatest grassroots campaign this country has ever seen.

O’Rourke joins a large and unsettled 2020 field in which his fundraising prowess, bipartisan optimism and anti-establishment attitude could quickly make him a political force.

His lack of governing experience could hurt, but President Donald Trump’s shock win in 2016 suggests that the US electorate is not afraid to select a charismatic outsider.

With reporting by AP