“In the past, the president has said he supports coal when coupled with technologies that prevent emissions from escaping into the atmosphere. His administration has invested in the development of clean-coal technologies, but the most effective technologies are generally expensive and unproven,” the report said. “Obama has been a much bigger champion of natural gas, a cleaner-burning alternative to coal that is seeing fast-rising production in the U.S.”

KOL, the coal ETF, is down about 20% this year despite the recent rally. Over 60% of the portfolio is in non-U.S. stocks, according to Morningstar. Trading volume in the ETF has been picking up since Romney made his coal comment during the first debate in early October.

President Barack Obama has been a proponent of clean energy. There are several ETFs in the category although they don’t have much in the way of assets. PowerShares WilderHill Clean Energy Portfolio (NYSEArca: PBW) is the largest with $122.4 million.

PBW is down about 4% the past month. U.S. Natural Gas Fund (NYSEArca: UNG) is off about 5%.

Market Vectors Coal