Climate change activists delivered petitions to Sen. Joe Donnelly's office urging the senator to reject a resolution that would repeal EPA regulations.

Environmental group the Sierra Club will launch digital and print ads this weekend pushing Democratic Sen. Joe Donnelly to oppose legislation curtailing the Environmental Protection Agency's new Clean Power Plan. He is being targeted as a potential swing vote in the Senate.

Indiana was part of an effort to block the EPA's power plant rule before it became final. The latest lawsuit - involving Indiana and 22 other states - takes aim at the regulation now that it's taken effect.