United States Senate contains different political parties
The Democratic Party is one of the two major contemporary political parties in the United States , along with the Republican Party . The Republican Party , commonly referred to as the GOP ( abbreviation for Grand Old Party ) , is one of the two major contemporary political parties in the United States , the other being its historic rival , the Democratic Party . United States House of Representatives . He or she and other floor leaders are chosen by the Democratic Caucus or the Republican Conferences , depending on whichever party has more voting members .