Christopher J. Van Hollen Jr. (born January 10, 1959) is an American politician serving as the junior United States Senator from Maryland since January 3, 2017. From 2003 to 2017 he served as the U.S. Representative for Maryland's 8th congressional district. He is a member of the Democratic Party. In 2006, Van Hollen became the chair of the Democratic Congressional Campaign Committee (DCCC). In this post, he was responsible for leading efforts to defend vulnerable Democrats and get more Democrats