The list of Democrats battling to oppose U.S. President Donald Trump in the 2020 election grew again Tuesday with Senator Bernie Sanders announcing he is joining the race.
Sanders tried to win the Democratic Party's nomination in 2016, but lost to former Secretary of State Hillary Clinton.
The 77-year-old gained a strong following with plans to make college tuition free and for the government to greatly expand its role in providing health care to Americans.
Sanders joins an already crowded field of Democrats who have announced their candidacy with still about a year before the 2020 primary elections begin.
Those candidates include fellow Senators Elizabeth Warren, Cory Booker, Amy Klobuchar, Kristen Gillibrand and Kamala Harris.
The senator from the northeastern state of Vermont announced his candidacy in an early morning email to supporters, asking for 1 million people to register to help launch a grassroots movement to counter special interests.
Sanders, a frequent critic of Trump, said in his email Trump was "the most dangerous president in modern American history." Sanders added: "We are running against a president who is a pathological liar, a fraud, a racist, a sexist, a xenophobe and someone who is undermining American democracy as he leads us in an authoritarian direction."
Sanders has been ranked among the leaders in opinion polls of prospective 2020 candidates, but he faces challenges from a large pool of other progressives who advocate for many of the same issues that he brought into the party's mainstream.
The crowded field of liberals could make it harder for Sanders to engender the same level of ardent support he received during his 2016 campaign. He also is likely to face questions about his age and his relevance in a party that is represented by a growing number of women and minorities, groups that Sanders struggled to win over in 2016.
Sanders also released a YouTube video Tuesday outlining major themes of his campaign.
