House members must be twenty-five years of age and citizens for seven years. Senators are at least thirty years old and citizens for nine years. Another difference is who they represent. ... Today, Congress consists of 100 senators (two from each state) and 435 voting members of the House of Representatives. The Speaker of the House acts as the leader of the U.S. House of Representatives. Every two years, the Members of the U.S. House of Representatives vote on the first day of each new Congress. The Senate Republican and Democratic floor leaders are elected by the members of their party in the Senate at the beginning of each Congress. Depending on which party is in power, one serves as majority leader and the other as minority leader. The leaders serve as spokespersons for their party's positions on issues.