WASHINGTON, D.C. — As President Obama mulls a possible troop increase in Afghanistan, Rep. Betty McCollum, D-Minn., cosponsored legislation this week that would impose a surtax to pay for the long-running war.

If passed, the measure would require President Obama to set a surtax to fully pay for the previous year’s war cost beginning in 2011.

McCollum was joined on the legislation by powerful members of the Democratic caucus, including the chairman of the House Appropriations Committee, Dave Obey of Wisconsin, and the chairman of the House Financial Services Committee, Barney Frank.

“For the last year, as we’ve struggled to pass health-care reform, we’ve been told that we have to pay for the bill - and the cost over the next decade will be about a trillion dollars,” Obey said in a statement. “Now the president is being asked to consider an enlarged counterinsurgency effort in Afghanistan, which proponents tell us will take at least a decade and would also cost about a trillion dollars.  But unlike the health-care bill, that would not be paid for.  We believe that’s wrong. Regardless of whether one favors the war or not, if it is to be fought, it ought to be paid for.”

Democratic lawmakers previously introduced similar legislation on the Iraq war. But it failed to pass through Congress.