Legislators look to four sources for their cues on how to vote on issues. First, rank-and-file party members usually try to support their party when they can, and partisanship has increased in recent years as each of the major parties has become more homogeneous. Second, the president is often actively engaged in trying to persuade legislators to vote his way. The views of the constituents back home are a third factor in how legislators vote. Finally, interest groups provide legislators with information on issues and their impact on the home district. These four influences push Congress in both the majoritarian and the pluralist direction.