Key Senate Democrats signaled yesterday they are willing to negotiate with Republicans on nuclear power and expanded domestic oil and gas development if it helps in nailing down the 60 votes necessary for floor passage on a comprehensive global warming and energy bill. "Every idea is on the table," said Foreign Relations Chairman John Kerry (D-Mass.), the lead sponsor of Senate climate legislation. "We're going to work in a bona fide way with everybody to see how to bridge a gap here. We've got to get a 60-vote margin. That means you've got to legislate, which means you have to compromise."