Though Republicans portray climate change legislation as a costly energy tax that would cost families thousands of dollars a year, the worsening economy and budget woes in dozens of states are increasing chances the Senate will enact a bill this year.

The White House is hoping billions of dollars worth of free emissions allowances that would be part of a cap-and-trade system will persuade undecided senators to support the bill, which is one of its top domestic priorities.

The climate change bill (HR 2454) the House passed on June 26 would distribute allowances from 2012 to 2025 to each state to protect consumers from energy price hikes, help utilities and other industries transition to clean energy and to spur conservation efforts and new technologies.

Analysts say if the allowances are incorporated into a House-Senate compromise, they could deliver between $120 billion and $330 billion worth of assistance to states, which would have substantial leeway to spend the money as they see fit. The largesse could prove to be a potent enticement at a time when national unemployment stands at 9.5 percent and many states are experiencing even higher jobless rates.