The White House late Tuesday again threatened a veto of a Senate bill to supplement a government program that helps poor families pay the energy costs of heating and cooling their houses, even though it’s unlikely the bill will be brought up for another vote this year.

Despite strong bipartisan support for the bill (S 3186), which would add an extra $2.5 billion in fiscal 2008 appropriations to the Low-Income Home Energy Assistance Program, or LIHEAP, efforts to enact the legislation were derailed last week when the Senate could not muster enough support to take it up.

Repeating the threat first issued July 26 is an effective warning to the House, where Vermont Democrat Peter Welch and others are trying to bring a companion measure to the floor in September.

A projected shortfall in LIHEAP funding has caused near panic in the Northeast, as residents brace themselves and their wallets to handle skyrocketing heating oil prices that are expected to outpace last year’s per-gallon rate by 50 percent.

The administration argues that the program is an unnecessary deficit spending measure, and points to about $100 million remaining in the program for use before the end of September.

But cold-weather states are eyeing other figures: 16 percent, the number of eligible families who actually received LIHEAP assistance in the last fiscal year, and about $500 million — the amount by which the president lowered his request for LIHEAP funding in fiscal 2009 — which together, suggest that the LIHEAP budget will be tighter in the winter ahead.

Since Congress is likely to rely on a stopgap spending measure to cover government operations until next year, residents of cold-weather states are pressuring their representatives to find a way to fill the gap in LIHEAP funding.

Republicans in the Senate have floated a counterproposal, which suggests offsetting the cost of propping up the LIHEAP program by repealing tax breaks to oil companies. But at this point, it appears that any financial influx to the program will have to be part of an overall energy package, or accounted for among other supplemental appropriations, in order to move through the Senate.