As the Senate lumbers toward passage of its healthcare bill, Democrats are looking ahead to the potentially difficult process of reconciling its substantial differences with the more liberal House version—the last major obstacle before President Obama can sign landmark legislation into law. Democrats are hopeful that the momentum generated by the long-awaited Senate vote—and the high political stakes involved in finishing the job—will grease the wheels of negotiations with the House. But after lawmakers enjoy what is left of the holiday season in their home states, they will return to wide and deeply held differences between the House and Senate bills on federal funding for abortion and the liberals' dream of establishing a "public option"—a government plan that would compete with private insurers—to guarantee access to affordable insurance. Negotiators also will have to hammer out disagreements that will determine how quickly the bill takes effect, what taxes will be raised, and other items that reach deeply into every hospital, doctor's office, and home medicine cabinet.