A bipartisan group of 60 Democrats and 40 Republicans in the House of Representatives has submitted a letter to Congress’ deficit reduction committee, urging the supercommittee to consider sacred cows, including entitlement cuts and new revenue, to achieve a deal that would make a major dent in the nation’s debt.

The letter represents a rare cross-party effort for the rancorous House, and its organizers said they hoped it would help nudge the 12-member panel to reach a deal that would far exceed the committee’s mandate to come up with $1.5 trillion in savings by Nov. 23.

Among those who signed were several dozen Republicans who had previously signed a pledge promising they would not support a net tax increase. Among the Democratic signers were several more liberal House members who have previously opposed entitlement cuts.

Rep. Emanuel Cleaver II (D-Mo.), chairman of the Congressional Black Caucus, said the effort was to help Congress avoid being “cornered by the paralysis of small potatoes.” Rep. Cynthia M. Lummis (R-Wyo.), a member of the conservative Republican Study Group, said the intent was to propel the supercommittee to craft a strategy “so big, so comprehensive, so inclusive that any great statesman or stateswoman could hardly resist voting for it.”

The letter comes as pessimism that the supercommittee can find agreement is running high on Capitol Hill. House Minority Whip Steny Hoyer (D-Md.), who signed on to the letter, acknowledged to reporters Wednesday that “expectations for the success of the supercommittee are low.”

Aides to both sides have said negotiations are continuing among the six House members and six Senators who serve on the panel, but that they are stuck on the same issue that has divided previous efforts to cut the deficit — Democrats want Republicans to accept sizable new revenue before agreeing to significant entitlement cuts and Republicans do not want to back a tax increase.

But Hoyer said the diminished expectations presented the group an opportunity to surprise the country and the economy with a success that could boost national confidence — and suggested the bipartisan effort by 100 members was a sign that a badly divided Congress wants to find success.

“To succeed, all options for mandatory and discretionary spending and revenues must be on the table,” the group wrote, adding that previous deficit reduction task forces have suggested a goal of reducing the debt by $4 trillion over the next decade.

“Our country needs our honest, bipartisan judgment and our political courage,” the letter continues. “Your committee has been given a unique opportunity and authority to act. We are prepared to support you in this effort.”

Many of the letter’s authors were self-described moderates who have called for compromise in the past — Democratic members of the so-called Blue Dog coalition or its Republican counterpart the Tuesday Group.

The letter also lacked specifics. It did not, for instance, pledge its signers to backing a tax increase, as many Democrats have urged, but merely urged that the committee consider revenue.

Still, Republicans said the number of members of their party who came on board was significant, given how many others had privately said they supported the letter’s aims but did not sign because they were afraid of being accused of backing a tax increase, particularly by Americans for Tax Reform President Grover Norquist. Norquist’s group urges elected officials to sign a promise not to support a net tax increase.

Rep. Steven C. LaTourette (R-Ohio) said that if he had a nickel for every fellow Republican who said they supported the letter’s goal but feared how Norquist would react, “I’d be rich and retired, and we’d have 200 signatures on the letter.”

For his part, LaTourette said he could be persuaded to back a net tax increase as part of a grand bargain that also included addressing racing entitlement growth and significant cut the nation’s debt.

Other Republicans who signed said the group had purposely not specified what revenue the supercommittee should include.

“The letter says revenue,” Lummis said. “It doesn’t say tax. It doesn’t say increase.”

The significance of the Republican call for revenue was downplayed by Norquist. In recent days, Democrats have worked to lay a possible supercommittee failure at Norquist’s feet, arguing Republican allegiance to his pledge has thwarted compromise.

“The committee is asked to consider all options,” Norquist said of the letter. “There’s nothing wrong with considering all options. Consider anything. Just don’t vote for a tax increase.”

The House effort matches a similar bipartisan push in the Senate, where 45 members have signed a letter urging the supercommittee to consider all options to get a deal that would far exceed its mandate, established in the August agreement that raised the debt ceiling.

“There’s always been a critique that there’s not a similar effort in the House,” said Sen. Mark Warner (D-Va.), an organizer of the Senate push. “Now we’ve got one.”