Was the senator most critical to getting climate legislation passed during this session a former senator?

As the health care debate rages on, senators are quietly moving downstream and upstream on climate.

Senator Dick Lugar (R-IN) drives a Prius, sequesters carbon on his tree farm, and voted for previous climate bills. Why is he now on the fence?

Quick. Which two states hold the largest single oil resource in the lower 48? If you’re thinking anywhere near Texas, you’re wrong.

Lindsey Graham is not the kind of senator you would expect to find on the climate fence. He is a Republican who has voted with his party 92 percent of the time during this Congressional session. Yet there he is.

The League of Conservation Voters notes that both Senators Stabenow and Levin have a similarly favorable environmental voting record. And both have spoken in favor of climate legislation. So what are they doing on the fence?

The fence for senators who are undecided about climate legislation is lined with conservatives and moderates, but Ohio's Sherrod Brown is decidedly liberal. What’s that about?

There’s been a flurry of movement around the Senate’s climate bill fence, including a probable “yea” that jumped to the undecided camp. That new fence-sitter, a Dem from Indiana, is our focus for today.

Sen. John McCain (R-AZ) had been like the Lone Ranger in the Senate working with his Tonto, Sen. Joe Lieberman (I-CT) to push for climate legislation. Suddenly, post the 2008 presidential campaign, he is on the fence.

For the second installment of our series on what senators on the fence are thinking about cap and trade, we turn to the senior senator from Tennessee: Lamar Alexander (R).