A major environmental group and a labor union are dropping $2.1 million in Michigan for a voter turnout operation aimed at lifting Democratic Rep. Gary Peters to the Senate.

The direct mail campaign from the League of Conservation Voters and the American Federation of State, County and Municipal Employees hopes to solidify Peters' slight polling edge over GOP candidate Terri Lynn Land, a former Michigan Secretary of State.

Peters was favored from the outset to replace retiring Democratic Sen. Carl Levin, but Land has made inroads in recent months and turned the race into a potential flip for Republicans. That in turn has drawn attention and money from worried left-leaning outside groups.

Following a similar strategy to national Democrats, the League of Conservation Voters is seeking to paint Land as being in the fossil fuel industry's pocket.

Peters, meantime, has attempted to burnish his climate credentials in the fairly moderate Midwest state, helping draw other groups, such as billionaire climate activist Tom Steyer's NextGen Climate Action PAC, into the race to slam Land on environmental issues.

"This campaign will ensure that voters learn the truth about Land’s extreme anti-environmental agenda," said Daniel J. Weiss, senior vice president for campaigns with the League of Conservation Voters.

For her part, Land has said that " climate change is absolutely real," but that she opposes Environmental Protection Agency regulations to curb emissions from power plants — which Peters supports — because she said they would be too economically burdensome.

But in a state with a strong union history that sustained some of the worst damage from the recent recession — not to mention another recession early in former President George W. Bush's administration — the joint League of Conservation Voters-AFSCME campaign is also seeking to tie Land to the billionaire industrialist Koch brothers in an attempt to portray her as beholden to big business and special interests.

“Terri Lynn Land has a record of standing with corporate CEOs and billionaires like the Koch brothers rather than workers in Michigan. Michiganders need a senator who will stand up for working families, and that certainly is not Terri Lynn Land,” said Seth Johnson, assistant political director with AFSCME.