Joe Biden said he was undertaking his third campaign for president to put an end to President Trump’s “aberrant” administration. He accused Trump of undermining American core values and threatening “the soul of this nation.” In a video posted on social media announcing his candidacy, Biden denounced Trump for asserting a moral equivalence between white supremacists and counter-protesters during a deadly gathering in Charlottesville, Virginia, in 2017. Trump later said there were “some very fine people on both sides” – an assertion that Biden said shocked him.

Accomplishments: After graduating from the University of Delaware and Syracuse Law School, Biden, at age 29, became one of the youngest people elected to the U.S. Senate, in 1972. He represented Delaware in the Senate for 36 years and twice ran for president in 1987 and 2007, but failed to gain much support from voters either time. After he dropped out of the presidential race in 2007, then-candidate Barack Obama asked Biden to be his running mate and the two went on to win the election. Biden served as Obama’s vice president for eight years.

Foreign policy: While in the Senate, Biden was a longtime member of the powerful foreign relations committee and served twice as the committee’s chairman. He opposed the Gulf War in 1991, but voted to authorize the invasion of Iraq in 2003. He advocated for U.S. and NATO intervention in Bosnia in 1994. While serving as vice president under Obama, Biden helped to formulate U.S. policy toward Iraq, including the withdrawal of troops in 2011. He also supported the NATO-led military intervention in Libya in 2011.

What sets him apart: Biden is the only Democrat running for president who has served as vice president and he has the national profile and name recognition that comes with such a job. He entered the race as one of the front-runners and has decades of experience with both national and international issues. However, because of his long time in the public sphere, he has a record of both successes and mistakes, and has become known for making verbal gaffes. His supporters hope his working-class roots from Scranton, Pennsylvania, can help him win over blue-collar Democrats who voted for Trump in 2016. Biden is also one of the oldest candidates in the race, younger only to Bernie Sanders, and if he won, would be the oldest person to ever be elected as president.

Platform: Biden is one of the few candidates who has a more centrist brand of politics and a reputation of reaching across the aisle to work with Republican lawmakers. However, Biden has pushed back against criticism that he is not liberal enough for today’s Democratic Party, saying at an event in March, “I have the most progressive record of anybody running.” Biden has emphasized the record of the Obama administration, including expanding health care, supporting efforts to legalize gay marriage, and the government bailout out the auto industry.