The bigger issue is not what's in the bill but how to pay for it. Pay-as-you-go rules mean that Congress has to find offsets for any additional spending it wants – over the $280 billion "baseline" projected if current policies continued.
House and Senate proposals use savings and new revenue from motley sources – customs and user fees, a credit-card compliance program that should improve collection of taxes, a change in brokerage reporting on certain securities transactions – but each house has issues with the other's proposed offset, either to pay for other upcoming bills or to avoid anything that smacks of new taxes, something the House has said is unacceptable.
A contentious disaster program
In addition, a few programs have become points of contention: The Senate wants $2.5 billion in tax credits for things like biofuels, conservation, and depreciation in the value of racehorses – an add-on that the House is balking at. The House proposed a bill that would include about $6 billion in new funding, but left off a $4 billion permanent disaster program that Sen. Max Baucus (D) of Montana, chair of the Finance Committee, has said is nonnegotiable.
As of Tuesday morning, an agreement still hadn't been reached, though Senator Baucus and Rep. Charles Rangel (D) of New York, chairman of the House Ways and Means Committee, were planning to sit together to try and hash out the differences.
The disaster program is controversial among observers, too.