Many Republicans years ago disputed the notion of global warming, but the political pendulum has shifted and congressional debate now generally focuses on how to fix it rather than whether it exists.

But the prospects of global warming legislation have taken some hits in recent months as the economy has soured.

Sen. Sherrod Brown (D-Ohio), a strong supporter of going green, wrestled with how to vote on the climate bill that came before the upper chamber last month. He ultimately decided to vote against cloture as the motion fell 12 votes short of the necessary 60.

At the time, Brown cited the economy in explaining his vote, saying the bill “needlessly may hurt my state because it fails to protect against what could be a policy that exports emissions rather than eliminating emissions.”

Likewise, soaring gas prices have caused some lawmakers to rethink their positions on drilling for oil and gas. Rep. Roscoe Bartlett (R-Md.) has reversed himself and now supports drilling in the Arctic National Wildlife Refuge (ANWR).

Former Rep. Jeb Bradley (R-N.H.), who is running for his old seat, has also altered his ANWR position and took heat about it during a GOP primary debate earlier this month.

“Finger-pointing isn’t going to help anyone,” Bradley said. “Conditions change and when conditions change, you have to change with them.”

Bradley is right. Politicians regularly attract criticism for changing their positions, but having the courage to shift publicly on certain policies is a strength, not a weakness. As the British economist John Maynard Keynes said, “When the facts change, I change my mind. What do you do, sir?”

Democratic leaders in Congress have not altered their position on drilling in ANWR, but have made drilling in various other parts of the United States a key talking point.

President Bush on Tuesday also shifted positions on the pending housing reform bills. Previously, his administration had vowed to veto both the House and Senate measures, though it now wants Congress to send a final bill quickly to his desk for him to sign.

It’s an election year, but when economic woes hit every part of the country, lawmakers and the president react accordingly. Earlier this year, Congress overwhelmingly passed an economic stimulus package that Bush praised. More is needed — perhaps another stimulus package as well as the housing bill.

How much more is necessary is not clear, though it is refreshing to see members on both sides of the aisle adapting to the circumstances around them.