Construction groups cheered when the joint chairmen of a high-profile fiscal policy panel called for a boost in the federal gasoline tax. However, they shouldn’t take the idea—floated by former White House Chief of Staff Erskine Bowles, a Democrat, and ex-U.S. Sen. Alan Simpson (R-Wyo.)—to the bank.

Bowles and Simpson, co-chairs of the National Commission on Fiscal Responsibility and Reform, released on Nov. 10 a draft proposal that includes the gas-tax provision, but the full commission has until Dec. 1 to vote on a final report.

Bowles and Simpson propose hiking the gas tax “gradually” by 15¢ a gallon, starting in 2013. The idea was endorsed by 15 construction, transportation and union groups as “bold but necessary.” Sens. Tom Carper (D-Del.) and George Voinovich (R-Ohio) on Nov. 5 asked the panel to recommend a 25¢-per-gal increase. But the Obama Administration and many in Congress have opposed a hike.

The overall Bowles-Simpson draft drew fire from House Speaker Nancy Pelosi (D-Calif.) on the left and the Americans for Tax Reform on the right.