WASHINGTON – The retail industry launched a new campaign Wednesday to protect a federal law that reduces the fees retailers must pay to banks every time a debit card is swiped, a move the industry hopes will blunt the massive lobbying attack from banks.

The campaign calls for hundreds of merchants to flood Capitol Hill in June for meetings with key lawmakers, the third “fly-in” to be held this year on the issue. It also includes print and radio ads in Washington and six to 12 key states, along with viral video clips. Industry executives say they expect the campaign to generate several thousand comments to lawmakers before the regulations on swipe fees, also known as interchange, take effect this summer.

“We’re going to raise the volume over the next 60 days,” said David French, chief lobbyist at the National Retail Federation, the trade group organizing the effort.

As part of the overhaul of the nation’s financial system last summer, Congress approved a measure that directed the Federal Reserve to revamp the way banks charge merchants for accepting debit cards. The Fed’s proposed regulations would lower the fees by as much as 70 percent, to 7 to 12 cents a swipe.

Financial firms from community banks to Visa and J.P. Morgan Chase have balked at the proposition and blanketed Capitol Hill with ads and advocates in recent months. Visa recently convened a global security summit to highlight fraud-prevention technology that it says is supported by the fees. This industry is pushing several bills that would delay implementation of the law.

Sen. Jon Tester, D-Mont., who sponsored one of the bills, said Wednesday that he is willing to shorten the proposed delay from two years to 15 months. That time frame — which Tester called the “bare minimum” — would allow six months to study the law, six months for regulators to draft new rules and three months for banks to implement them.

“I’m asking that we take a closer look so we can get the information to understand the impacts both intended and unintended,” he said.

The move was a bid to build support for his proposal, which faces an uncertain fate in the face of vigorous opposition by Senate majority whip Richard Durbin, D-Ill., sponsors of the original law. Retailers have said that waiting to implement the law is tantamount to killing it.