Former Pennsylvania Governor Ed Rendell said Tuesday that the current drop in gas prices could significantly dampen one of the GOP's major economic talking points against President Barack Obama -- but only if prices remain low through November.

Rendell, who has emerged as a key Democratic Party spokesman on infrastructure investment, made his remarks as a conference committee in Congress continues discussing how to fund an extension of the federal transportation bill. He and other transit advocates argued the final bill passed out of Congress should avoid any drastic changes to public transportation.

For months, the GOP has been hammering Obama with dubious claims that high gas prices are somehow related to the Keystone XL pipeline. The price drop, said Rendel, "removes what is probably the most serious negative in the the economic picture today."

"It wipes that issue away, and that's a huge plus to the president," he said. But he also noted that will only be the case "if the drop continues all the way to November."

For Rendell and other transportation advocates, falling gas prices are not a reason to skimp on mass transit in the next federal transportation bill. At $3.73 per gallon on average, gas may cost 17 cents less than it did just a month ago -- but boosters say public transportation is habit-forming and that even temporary drops in gas prices can create loyal bus and subway riders.

"While commuters are initially drawn to public transportation because of gas spikes, they remain public transportation users as prices fall," said Michael Melaniphy, the president of the American Public Transportation Association, on a conference call with Rendell.

APTA released an analysis on Tuesday projecting that even if gas prices fall back to their 2011 average of $3.52, public transportation would still see an increase of 200 million riders this year.

Over the long run, said Rendell, "gas prices are going to continue to rise." But that isn't the only thing that will keep people out of their cars, he argued.

"There's also the congestion factor. Congestion on America's highways and roads has almost reached an intolerable level," he said. Rendell and the heads of local transportation system heads on the call encouraged Congress to see the transportation network as a system, where mass transit offered drivers an additional choice in times of high gas prices.

Advocates are hoping that the final product of the long-delayed federal surface transportation bill -- which has now been extended nine times since September 2009 in lieu of fresh legislation -- will keep funding levels for public transportation steady. The Senate's bipartisan bill, which would do so, passed on a 74-22 vote in March. House Republicans, however, have signaled they would prefer to see guaranteed funding levels for public transportation, pedestrian facilities and bike paths stripped away.

As cars become more efficient and people drive less, the National Highway Trust, which funds the largest chunk of transportation programs, is going bankrupt. Because of that budgetary pressure, the Senate bill simply keeps transportation funding level -- despite mounting infrastructure spending needs.

"The best that we can afford at this point is to do no harm," said Rendell. "But in 2013, it seems to me the Congress and the administration have to come to grips with [infrastructure] problems."

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