FILE - This April 28, 2010, file photo, shows the Colstrip Steam Electric Station, a coal-fired power plant in Colstrip, Mont. President Barack Obama’s plan to cut carbon dioxide pollution has

... more 

FILE - This April 28, 2010, file photo, shows the Colstrip Steam Electric Station, a coal-fired power plant in Colstrip, Mont. President Barack Obama’s plan to cut carbon dioxide pollution has opened a new front in Montana’s U.S. Senate race as the general election campaign kicks off between Democratic Sen. John Walsh and Republican Rep. Steve Daines. Daines, fresh off his Tuesday night primary victory, planned to meet with business leaders in Billings on Wednesday, June 4, 2014, and later travel to Colstrip, home of the second largest coal-fired power plant west of the Mississippi River. Colstrip figures to be a likely target in draft rules from the Environmental Protection Agency that call for reducing Montana emissions 21 percent from recent levels by 2030. It delivers power across the Pacific Northwest and is Montana’s single largest source of carbon dioxide, a gas blamed by scientists for causing global temperatures to rise. (AP Photo/Matt Brown, File)

less 
1 / 28
Associated Press
Thu, Jun 5, 2014 12:15 AM EDT