Sen. Arlen Specter (D-Pa.) says he will vote for cloture on climate legislation, which would allow the bill to move to a simple majority vote.
Specter's comments last Friday are significant because they put the moderate lawmaker, who switched parties this year, on record opposing a filibuster of the plan that Democratic leaders want to consider this fall.
Backers of the bill to impose mandatory limits on greenhouse gas emissions will in all likelihood need 60 votes to go forward with the measure under Senate rules, and the comments put Specter in favor of allowing this to occur.
Speaking before the liberal Netroots Nation conference in Pittsburgh, Specter said he generally backs cloture -- or cutting off debate -- on Majority Leader Harry Reid's (D-Nev.) efforts to proceed with several measures.
Asked if he specifically would back allowing up-or-down votes on climate, labor and health care bills, he replied "Yes, no doubt about those three issues at all."
While he did not say how he would vote for final passage of a climate bill, a cloture vote is the bigger hurdle for supporters of the measure.
Specter's political party switch in April and the subsequent seating of Sen. Al Franken (D-Minn.) have given Senate Democrats 60 votes, the same number needed to beat back filibusters.
However, this by no means ensures that climate legislation can win enough votes to proceed, with views on the issue often breaking along regional as well as partisan lines.
Specter's comments in theory allow for wiggle room. Asked about voting for cloture on Democratic bills in general, he noted, "I would expect to support Senator Reid on a bill he wants to bring up to cut off debate on a motion to proceed so the issue could be taken up."
Under the Senate's complex procedures, legislation may require one cloture vote on a so-called motion to proceed to formally consider the bill, and a subsequent cloture vote to move to a simple majority vote on final passage. However, the moderator at the conference then asked Specter whether he would vote for cloture to have "up or down" votes, and Specter said he would.
Pressure on some Democrats
Specter is among a handful of Senate Democrats facing particularly heavy political pressure on climate change, as they must run for re-election in a coal-reliant manufacturing states.
A fifth-term senator, Specter faces both a primary challenge from Rep. Joe Sestak and likely general election match-up with former Rep. Pat Toomey (R), a conservative who has already come out against the cap-and-trade bill.
Though recent polls show Specter ahead of Sestak in a primary matchup, the Netroots convention featured a decidedly liberal crowd that also generally strongly supports President Obama’s political agenda. Sestak beat Specter in a straw poll held at the convention, capturing 46 percent of the vote compared to 10 percent for the incumbent.
Supporters of a climate bill called Specter's comments a good sign ahead of anticipated debate on a broad energy and climate change bill.
"Having Senator Specter indicate that he will support allowing an up-or-down vote on a clean energy or global warming bill is another very positive development," said Daniel Weiss, director of climate strategy for the Center for American Progress. "It is another positive sign that progress is likely to be made this fall."
Weiss noted Sen. Sherrod Brown's (D-Ohio) comment last month that he does not plan to back a filibuster of climate legislation. Brown's comment was reported on the liberal blog and news site Talking Points Memo last month.
However, both Brown and Specter are among the 10 Senate Democrats who signed a letter this month indicating that their support hinges on inclusion of trade-related provisions that they believe are needed to protect the manufacturing base in their states.
Reporter Alex Kaplun contributed to this report.