Updated

Democrats in Congress increasingly are putting pressure on Wall Street speculators to pull back from the oil markets, effectively blaming them for the unseasonable spike in oil and gas prices -- which has caused a headache for the White House as well as cash-strapped families.

For weeks, Republicans have called for more domestic oil production while Democrats push anew for clean-energy investment. It's the same fight that plays out almost every time gas prices surge, and one that is particularly shrill in an election year.

But as President Obama argues there's little his administration can do in the short-term to ease the pain at the pump, congressional Democrats this past week claimed federal regulators could have an effect by cracking down on Wall Street.

"We have a responsibility to ensure that the price of oil is no longer allowed to be driven up by the same Wall Street speculators who caused the devastating recession that working families are now experiencing," wrote 70 lawmakers in a letter to the Commodity Futures Trading Commission.

Investors like hedge funds are big players in the oil markets, bidding on futures contracts and potentially affecting the price of oil. How big of an impact those speculators have, and whether they actually serve a constructive purpose, is a matter of fierce debate.

More On This...

    Bart Chilton, a commissioner on the CFTC, told Fox Business Network that speculation alone adds an average of 56 cents to a gallon of gasoline. He estimated that's an extra $7 every time a driver fills up a Honda Civic.

    "We can cap the concentration that speculators can have in these markets. ... That is driving up prices," Chilton said.

    The CFTC was mandated by Congress, under the financial regulatory overhaul, to impose such limits on speculators. Those rules, though, are being challenged by the financial industry.

    Investors claim that Wall Street has been made into a scapegoat, and that basic supply-and-demand forces are at work in rising energy prices.

    "Trade is not to blame for this," investor and former actor Wayne Rogers told Fox News on Saturday. He added that the Democrats complaining about speculators are the same ones who speak out against the Canada-to-Texas Keystone pipeline, claiming that project would help relieve part of the problem.

    Chilton reasoned that the problem isn't the existence of speculators but the sheer concentration of them in the marketplace.

    "You can't have markets without speculators. Speculators are good. But there gets to be a level at which they can push prices around," he said. Chilton said he hopes the commission can have new rules in place by Memorial Day, but said he'd have to "cross my fingers."

    A recent report from the Federal Reserve Bank of St. Louis claimed speculators do have an impact in the price fluctuation.

    Between 2004 and 2008, according to the report, speculation "contributed around 15 percent to oil price increases in this period."

    The report found that global demand was the biggest driver of cost, with speculation as the "second most important driver."

    According to the Obama administration, the latest increase in oil and gas prices stems from both an increase in demand -- a product of a recovering economy -- and threats of a disruption in supply out of Iran.

    The average price of a gallon regular gas is at roughly $3.78.

    Still, while rising fuel prices can be a product of a recovering economy, they can also impede it.

    As Democrats focus their ire on speculators, Republicans say taking steps like reducing regulation and approving the Keystone pipeline could make a difference.

    Jack Gerard, CEO of the American Petroleum Institute, blamed high prices on "weak energy policy" at a Republican-held House hearing on Wednesday. He said more drilling could put "downward pressure" on prices.

    "The market forces driving crude higher are challenging, but America doesn't have to be held captive to them," he said, adding: "Supply matters."