NEW BRITAIN — Saying he was pleased to root the Export-Import Bank debate "right here on the factory floor," Sen. Chris Murphy thanked Mario Francalangia, whose family owns B & F Machine Co., for inviting him and Sen. Richard Blumenthal to speak Friday.

The federal agency, known as the Ex-Im Bank, largely offers guarantees on low-interest loans to foreign customers of U.S. companies. Boeing is by far the biggest beneficiary, which means indirectly, General Electric Aviation and its suppliers benefit, and to a lesser degree, Pratt & Whitney does as well.

As of July 1, the bank's charter expired and it hasn't been renewed, as libertarians and Tea Party Republicans say the bank, begun in 1934, should end because its loans amount to corporate welfare.

GE's advocacy for the bank was what motivated Francalangia to fly to Washington to lobby for the bank earlier this year. B & F makes many parts used in GE engines.

"B & F isn't a recipient of Ex-Im financing," Murphy said. "But your customers are."

Or at least, the customers of the company's customers are.

A large portion of B & F's 210 workers listened to Blumenthal and Murphy talk about their support for the Ex-Im Bank during their lunch break. Some workers were already aware of the Ex-Im Bank controversy.

"I read in the papers on and off," said Roberto Riccini, who joined B & F after selling his own machine shop seven years ago.

The Democratic senators said the bank has the votes for renewal. In fact, Blumenthal said it would be a landslide. But because the House speaker won't bring it up, "This fight is a tough political battle," Blumenthal said. "The outcome is by no means clear. It could go either way."

Blumenthal added, "The Koch brothers say this is another example of the big, evil federal government picking winners and losers. We need to pick winners, not because they're personal favorites, or they're backed by special interests, but because they're job creators."

Blumenthal said the subsidized financing is a way of leveling the playing field between Boeing and Airbus, which receives what he called direct subsidies. When asked whether $400 million in Connecticut tax credits for United Technologies Corp. and $900 million in South Carolina incentives to Boeing for opening a factory aren't also subsidies, he said those tax breaks "are like the little leagues" compared to other countries' corporate subsidies.

"This is an ideological fight within the Republican party," Murphy said. "Moderate Republicans are largely for it. The Tea Party wants it gone." Murphy said Republican leadership doesn't want to bring a bill renewing the program to the floor, because the vote would expose that split.

The fight is one that's obscure to most voters, even those whose jobs are being held up as dependent on the renewal. Many workers at the factory, unable to hear Blumenthal and Murphy, were left wondering what was going on.

"I never heard of the Ex-Im Bank before," said Ron Bell, who programs CNC machines for the firm.

Murphy said that Sikorsky and other manufacturers in Connecticut "can't export without the financing."

But while Sikorsky is certainly a heavy beneficiary of the bank's services, its commercial helicopters, which are the overwhelming majority of those financed with these deals, have been built in Pennsylvania for years.

The flow of money through the bank also makes for a complicated argument about exports vs. corporate support, in some cases at least.

Over the last two years, the Ex-Im Bank provided $519 million in guarantees for Sikorsky helicopter sales to a new helicopter leasing company in Ireland; $56.6 million in support for helicopter sales to Mexico; and $66.4 million for helicopter sales to Brazil.

The Irish company, Milestone Aviation, has since been bought by GE Capital. According to CorporateJetInvestor, Milestone was registered in Bermuda "but based in Dublin to benefit from tax breaks and Ireland's numerous double-taxation treaties."

Before GE Capital bought Milestone, its CEO worked in Ireland, but its president, general counsel and chief operating officer — all co-founders — were based in Columbus, Ohio.

Murphy said the fact that 90 percent of the companies whose customers use the financing are small businesses means it's unfair to say the Ex-Im Bank is corporate welfare. He said even when a big business like United Technologies Corp. or General Electric benefits, that work flows down to the supply chain.

Sandro Quercia, one of six family members working at B & F, said he knew Mario Francalangia, his cousin, was recruited to fly to Washington, and he said, "I know the people we do business with are for it."

And if his customers are for it, he's for it.