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How are those new Walmart discounts working out for you? Still waiting for the price of taquitos to drop at 7-Eleven?

No? Good, because convenience store owners and other retail outlets say the break they planned to give consumers isn't coming if efforts on Capitol Hill succeed to delay by two years a proposed cap on debit card swipe fees.

The provision, one of the "consumer-friendly" measures adopted in President Obama's Wall Street overhaul last year, was supposed to go into effect in July. But that could be put on hold as small merchants and behemoth financial firms battle over proposed regulations that would alter the formula that banks charge for retailers to provide the convenience of swipe cards.

According to the preliminary proposal by the Federal Reserve put forth in December, the Federal Reserve would reduce debit card swipe fees from their current level of 1 to 2 percent of each transaction to a flat fee of no more than 12 cents per transaction -- a 70 percent reduction in the $20 billion-a-year practice that would eat into the profits of card networks Visa and MasterCard as well big banks such as Citigroup and JPMorgan Chase.

The proposal, which exempts banks with under $10 billion in assets, came after merchants persuaded lawmakers last year to give the Fed power to set the fees at "reasonable" levels. The final proposal is expected in April.

But banks, credit unions and other financial firms have launched a counteroffensive to stop its implementation, and has mobilized trade groups and an army of lobbyists on both sides and cost millions of dollars.

That appears to have won over a group of nine bipartisan lawmakers who want to delay the fee cap for two years and implement a one-year study on the law's impact.

"The stakes are simply too high to move forward with this rule without a closer look at the impact on consumers, credit unions, community banks and the small businesses and jobs they sustain," said Sen. Jon Tester, D-Mont., a member of the Senate Banking Committee. "That is why we need to make sure we stop and study these proposed rules before implementing anything."

But in the House, Reps. Peter Welch, D-Vt., and Bill Shuster, R-Pa., on Wednesday sent a letter to their colleagues arguing that the bill will harm merchants and small businesses.

"Year after year, the credit card industry has extracted billions of dollars in fees from small businesses around the country," Welch and Shuster wrote. "Visa and MasterCard cash in every time a credit or debit card is swiped, leaving small businesses and consumers to pay the tab. We urge you to keep these facts in mind when you are asked to support a delay in protections for merchants and small businesses from out-of-control debit card swipe fees."

The National Retail Federation, a trade group that represents more than 1.6 million American companies, opposes any delay, saying it would prevent retailers from giving discounts to consumers who use debit cards, among other benefits, and would cost merchants and the public more than $1 billion per month.

"We are extremely surprised to see a bill introduced that favors Wall Street banks and price-fixing card companies over Main Street merchants and their customers," NRF Senior Vice President and General Counsel Mallory Duncan said. "Merchants are ready to pass lower swipe fees along to consumers in the form of discounts and other benefits as soon as reform goes into effect July but we can't do that if Congress lets bankers stand in the way."

The Merchants Payments Coalition, a trade group that represents 2.7 million convenience stores, retailers and small business owners, also slammed the bill as a repeat of the Troubled Assets Relief Program, or TARP, that is credited with saving big banks from failure after their near implosions of 2007-2008.

"This bill is just another Wall Street bailout," said Pat Lewis, who owns 13 convenience stores in Idaho. "The Tester bill is TARP 2, when the last thing we need is another handout to the big banks."

In 2009, consumers used debit cards in nearly 38 billion retail transactions valued at $1.45 trillion, according to the Federal Reserve. Banks collected on average 44 cents in debit card swipe fees that year --  slightly more than 1 percent of each sale, which adds up to about $16 billion.

While the Fed says that's too high, banks argue the proposed changes do not guarantee that retailers will pass savings on to consumers and that they could just boost the bottom lines of mainly a handful of large retailers like Walmart.

Financial firms also say the Fed's proposal could end up costing consumers other ways.

"If financial institutions have to cover all of the costs or virtually all of the costs of debit, they will have to make it up somewhere," said Bill Hampel, senior vice president at the Credit Union National Association and spokesman for the Electronic Payments Coalition. "And the most likely way to make that up is through increased fees on the consumers who use the debit cards. So that could be things like a monthly fee to have access to a debit card or a per-transaction fee."

Fox Business' Peter Barnes contributed to this report.