House Democratic leaders were struggling Thursday to contain uprisings on the hot-button issues of abortion and immigration that have left them little margin for error as they attempt to push through a massive healthcare reform bill this weekend. Although confident of victory, House Speaker Nancy Pelosi and other Democratic leaders were working to limit defections to the roughly 25 Democrats viewed as "hard no" votes. For party leaders, setting a weekend deadline for passage represented a calculated risk, one that could backfire if the vote—now expected late Saturday or Sunday—fails or must be delayed. But they feared that if members were given more time to consider the legislation, new issues could arise, particularly as lawmakers digest the results from Tuesday's elections.