Denver Post: Beleaguered and battered, congressional Republicans have been rolled on the budget and on the stimulus. They face daunting Democratic majorities in the House and the indignity of Arlen Specter’s defection in the Senate. But the minority party has found hope in the fight over a mechanism to reduce greenhouse gases, which, if it fails to pass Congress, could topple the Democratic vision on both energy and the environment. House Democrats on the Energy and Commerce Committee are …