No Room For Error As Democratic Majority Slims Tight numbers could plague the Democratic majority for months, but top Democrats insist they can hold their caucus together. By: Nathaniel Reed and last updated 2021-04-15 19:36:00-04 Since the start of the 117th Congress, six seats in the House of Representatives have become vacant â creating a razor-thin Democratic majority trying to pass ambitious legislation, including a $2 trillion infrastructure package. Of the vacancies, four are Democrats, three of whom resigned Congress to join the Biden Administration. The fourth, 15-term Congressman Alcee Hastings, died earlier this month after a battle with pancreatic cancer.