His campaign contends that Obama would be better for coal than rival Mitt Romney, and the commercial highlights the Republican saying in 2003 that he wouldn't back a coal-fired plant "that kills people."
Romney accuses Obama of imposing regulations that would "bankrupt" the coal industry. He promises that the United States will become energy independent by 2020 through more aggressive exploitation of domestic oil, gas, coal and other natural resources. The Republican also vows to pursue measured reforms of environmental laws and regulations without impeding jobs or industries.
Anti-Obama commercials on the radio in Ohio use the president's 2008 remark that if someone wants to build a coal-powered plant, they can go ahead, but "it's just that it will bankrupt them." The tagline says "let's cap Obama and trade him for Mitt Romney."
The United Mine Workers of America, which endorsed Franklin D. Roosevelt in 1936, John F. Kennedy in 1960 and Obama in 2008, has declined to back a presidential candidate this year, saying it doesn't see either Obama or Romney offering the best opportunities for its members.
For Manchin, support for coal is personal, business and political commonsense.
In the early morning of Nov. 20, 1968, an explosion at the Mountaineer Coal Co. mine in Farmington, W.Va., killed 78 miners. Among the dead were Manchin's uncle, John Gouzd, and high school friends.
In the years since, Manchin owes some of his wealth to Enersystems Inc., a coal brokerage firm he once helped operate. Manchin's financial disclosure forms in 2009 and 2010 showed operating income of more than $1.7 million.
West Virginia is the second-largest coal producing state behind Wyoming and its mines and plants add up to more than 21,000 underground and surface jobs, according to the Energy Department. Coal mined in Appalachia generates electricity, is shipped overseas and is used in metal production.
Manchin has repeatedly challenged the Obama administration over coal. In 2010, as West Virginia governor, he sued the EPA over its crackdown on mountaintop mining.
"Enough is enough," Manchin said this past June. "The people of West Virginia are tired of the EPA's overreach, and I will do everything in my power to rein in the EPA — and any agency that oversteps its authority."
The Democrat has consistently voted with Republicans for legislation to roll back EPA rules.
Yet, in the one and only Senate campaign debate earlier this month, Manchin repeatedly had to defend himself against criticism from Republican rival and businessman John Raese, who tied the Democrat to Obama.
"Who controls the environmental rules, that's the executive branch and that's handled by his quarterback, Barack Obama," said Raese, delivering his rhetorical stabs with the smooth voice of a late-night deejay on one of his radio stations. "Joe's heart ... is in the right place. I'm not saying it's not. I'm just saying the team that he's on has no interest at all in helping West Virginia. The only interest they have is getting us out of the fossil fuel business."
Manchin insisted he would fight for coal, no matter what.
"The government should be your partner. It shouldn't be your adversary," he said on the debate stage at Shepherd University in Shepherdstown, W.Va. "It should be your ally and that's what we don't have in Washington and that's what I've been working for. And I'll work with whoever the president. I worked when President Bush was there. I worked with President Obama. I will work with the next president."
West Virginia voters are expected to give Manchin a full six-year term in November. Obama lost the state in 2008 by 13 percentage points and in this year's Democratic primary in May, a convicted felon in Texas got 40 percent of the vote to the president's 60 percent, a fresh reminder of Obama's unpopularity in the state. Romney is expected to handily win West Virginia's five electoral votes next month.