Democratic senators are trying to force the GOP to get 60 votes to repeal Obamacare, a tall task for Republicans that only have a two-seat majority in the chamber.

Sen. Tim Kaine, D-Va., and Patty Murray, D-Wash., introduced an amendment to a budget resolution that would thwart Republican plans to repeal the healthcare law via a simple majority vote instead of the 60 votes needed to break a filibuster. The effort comes as Democrats and Republicans spar over plans to repeal Obamacare but leave it intact for a few years while a replacement is crafted.