Aside from Mitt Romney's recent jab at Barack Obama's concern over global warming—and the president's tit-for-tat response—climate change has been largely under the radar in the campaign. But several groups, backed by hundreds of thousands of petitions, are trying to change that, at least for one night. Nine environmental organizations Friday delivered more than 160,000 petitions to Jim Lehrer urging him to ask a question about climate change during Wednesday's first presidential debate.