Beto O'Rourke Joins Democratic Presidential FieldFormer U.S. congressman Beto O'Rourke on Thursday joined the crowded field for the Democratic Party's nomination to oppose President Donald Trump as he runs for re-election in 2020. O'Rourke, who served three terms in the House of Representatives before losing a close contest for a Senate seat last year in Texas, released a video message pledging a positive campaign that embraces the opportunity of facing challenges at what he called a "moment of maximum peril and maximum potential." "This is a defining moment of truth for this country and for every single one of us," O'Rourke said seated alongside his wife Amy. Later, he visited Iowa, where the party's first presidential nominating contest will be held in February 2020, meeting with voters in a restaurant in the small city of Keokuk.\n\nWATCH: Beto is in the race No media source currently available More than a dozen Democrats are seeking the party nomination to run against Trump, with O'Rourke saying that any one of them "would be far better than the current occupant of the White House." In answering questions, he staked out progressive positions similar to other Democrats, calling for "guaranteed" universal health care, decisive actions to combat the effects of climate change and an end to the federal government's prohibition on the use of marijuana. In the video he released earlier, he also highlighted criminal justice reform and ending U.S. involvement in decades-long wars as some of his priorities. "Perhaps most importantly of all, because our very existence depends on it, we can unleash the ingenuity and creativity of millions of Americans who want to ensure that we squarely confront the challenge of climate change before it's too late," O'Rourke said. And he said that if immigration is a problem, then it is the best problem the United States could have, calling for legal paths for immigrants "to work, to be with family and to flee persecution." O'Rourke joins the long list of Democrats who want to challenge Trump in the November 2020 vote. Those who have already announced include Senators Cory Booker, Kirsten Gillibrand, Kamala Harris, Amy Klobuchar, Bernie Sanders and Elizabeth Warren, as well as Representative Tulsi Gabbard and former Housing and Urban Development Secretary Julian Castro. Former Vice President Joe Biden has signaled he appears ready to join the field, with some early polling suggesting he would lead the Democratic field at this early date in the nominating process.\n\nO'Rourke lost last year's Senate race by less than three percentage points to incumbent Republican Sen. Ted Cruz, but political analysts considered that as a credible showing in a conservative state like Texas.  Read  profile Compare all of the 2020 Democratic candidates Explore the 2020 candidates: Check out our profiles of the Democratic candidates and see what sets them apart.