Scenario No. 2: The Senate approves the deal, the House amends it, and gridlock ensues.

If Democrats change as much as a comma in the deal, congressional Republicans could walk away. It is especially noteworthy that some powerful players on the right, including Sarah Palin, Glenn Beck and Rush Limbaugh, are opposed to the plan.

Government scorekeepers say the bill costs $857.8 billion over 10 years, more than the 2009 stimulus.

That price tag could go higher if Democrats change the unemployment benefit provisions.