Administration officials have stressed for weeks they are comfortable with negotiators using the House-passed bill as a starting point, but the activists closest to the issue say that's not enough.
Testifying today are Energy Secretary Steven Chu, EPA administrator Lisa Jackson, Interior Secretary Ken Salazar and Jon Wellinghoff, chairman of the Federal Energy Regulatory Commission.
Climate chief Lord Stern last week in London suggested he wasn't worried about whether Obama would personally attend the Climate Change Conference in Copenhagen.
"These meetings are always structured, just as Kyoto, to be held at ministerial level. We are not writing anything off or foreclosing possibilities but we treat this as a ministerial meeting in the first instance and if the kind of progress is made that would warrant the attendance of leaders then certainly we would consider that," Stern said.
With health care ramping up, it's unlikely the climate bill would reach the Senate floor this year. (The 923-page bill is posted here if you want to read it.)
Here's Boxer (D-CA) previewing the hearings: