Bloomberg News
Bernie Sanders

Vermont Democratic Sen. Bernie Sanders, 77, announced Tuesday he will run for president in the 2020 campaign. 

Sanders made the announcement through an email to supporters after an interview on Vermont Public Radio. His email read, "I am asking you to join me today as part of an unprecedented and historic grassroots campaign that will begin with at least a million people from across the country." 

Sanders' bid for the Democratic nomination for president in 2016 fell short against former Secretary of State and New York Sen. Hillary Clinton. 

Democratic candidates Sanders will go up against are New Jersey Sen. Cory Booker, Minnesota Sen. Amy Klobuchar, Massachusets Sen. Elizabeth Warren, South Bend, Indiana Mayor Pete Buttigieg, California Sen. Kamala Harris, New York Sen. Kirsten Gillibrand, former U.S. Secretary of Housing and Urban Development Julian Castro, Hawaii Representative Tulsi Gabbard, former West Virginia Sen. and U.S. Army Paratrooper Richard Ojeda, and former Maryland Congressman John Delaney. 

Much of Sanders' grassroots 2016 campaign centered on free college tuition, healthcare reform, campaign finance reform, banking system reform, and other progressive agendas.