On November 8, 2016, Republicans won the presidency and retained control of the US House and Senate in Congress. The composition of the Senate shift will profoundly affect the passage of new legislation. With only 52 Republicans in the Senate, the Republican Senate leadership will have to ensure that all Republicans support any legislation because a few defections on an issue could push them into a minority position. More challenging is that except for budget-related legislation, which can pass with only a simple majority, other legislation, including much of an Affordable Care Act (ACA) replacement bill, will require the support of 60 votes in the Senate to circumvent a filibuster.
Wilensky GR. The Future of the ACA and Health Care Policy in the United States. JAMA. 2017;317(1):21-22. doi:10.1001/jama.2016.18762