By Adam O'Neal - September 2, 2014

The United Mine Workers of America waded into the Senate race in West Virginia Monday, endorsing Democratic candidate Natalie Tennant.

“Don’t let anyone fool you -- Natalie Tennant is standing with coal miners again in our fight against the EPA’s rules that threaten our members’ jobs, our retirees’ security, and our communities’ ability to survive,” said UMWA International president Cecil E. Roberts in a statement.

The endorsement could provide a boost for Tennant, who has trailed her opponent, Rep. Shelley Moore Capito, in fundraising and polling. Tennant told supporters in an e-mail that the endorsement was “big news” and “huge” for the campaign.

"While I am fighting to protect coal jobs and keep our miners working, I will fight just as hard to keep them safe, and protect the health care and pensions they have earned over a lifetime [of] work,” added Tennant, who has accused Capito of opposing coal miner protections in the past.

In West Virginia, proving one’s pro-coal bona fides is crucial to winning any significant office.

The Capito campaign pushed back Monday, citing Tennant’s previous support for President Obama’s re-election campaign as evidence that she had undergone a “coal evolution.”

“Hard-working West Virginia coal miners know that Shelley Moore Capito is the only candidate in this election fighting on their behalf every single day,” said Capito spokesperson Amy Graham. “Shelley led the fight for the most significant update of mine safety laws since the 1970s and she worked alongside the UMWA to protect miners’ healthcare and pensions.”

While a major union endorsement is helpful in the coal-rich state, Capito remains the strong favorite to prevail in November. The RCP polling average shows the seven-term congresswoman leading the West Virginia secretary of state by 14 percentage points.

The candidates appeared onstage together last week at a forum hosted by the West Virginia Chamber of Commerce. They will formally debate Oct. 7 in Charleston.

The union announced its endorsement of Tennant at a Labor Day rally in Racine.