Republican efforts to cut spending and extend popular tax cuts suffered dual setbacks yesterday, as opposition from within the party forced congressional leaders to delay votes on both fronts.

With a Senate vote on tax cuts and a House of Representatives vote on spending cuts both postponed, the move marks a high-profile failure to rally the Republican majority around key planks of its platform. Coming straight after Democratic victories in elections for governor this week in New Jersey and Virginia, the setbacks added to a sense of Republican unease on Capitol Hill.