An array of big guns lined up to fire at Congress yesterday, with Boston Mayor Tom Menino, State Attorney General Martha Coakley, Lieutenant Governor Tim Murray and Secretary of Housing and Urban Development Shaun Donovan speaking at an event at in Dorchester to demand that Congress pass several bills aimed at helping underwater borrowers.

Three bills currently in Congress each tackle slightly different aspects of the problem, but in sum they would allow underwater borrowers — those who are current on their mortgage but who can’t refinance because their house’s value has declined — to refinance, enabling them to take advantage of today’s low rates. One of the bills, sponsored by Sen. Jeff Merkley (D-Oregon), would also provide additional federal funds to help pay for closing costs.

Proponents argue that the bills would provide a boost to the economy and help stabilize the housing market by lowering people’s payments and/or allowing them to rebuild equity faster, helping to prevent future foreclosures. The decrease in the foreclosure rate would result more than cover the costs of the bills to taxpayers, Donovan said.

"We have the lowest interest rates in the history of the 30-year mortgage, yet we have millions of families who have been locked out from refinancing because they [are] underwater," said Donovan. "Here in Massachusetts…it’s still one in six families underwater. The average family could save up to $3,000 dollars a year [though refinancing]."

The politicians were applying pressure to get the bills passed next month, before Congress recesses again ahead of the November presidential election.

"There are some opportunities left on the president’s to-do list," said Murray.