Sen. Warren B. Rudman (R-N.H.) beamed at the audience of real estate developers gathered in a glitzy hotel ballroom one evening this week, and cheerfully announced that he had bad news: Some of them were going to pay more taxes.

There were boos and groans as he broached the most unpopular subject in the room: The sweeping tax-overhaul bill the Senate will begin considering next week.

But minutes later, the mood changed. Rudman gave the tax package a ringing endorsement, calling its reductions in tax rates and limitations on deductions "one of the most remarkable pieces of work in a long time. It is a very fair bill." And, Rudman said, it would promote real estate deals, not for tax reasons, but on the basis of economics.

In the back of the room, a few hands clapped. Then others joined in, and suddenly members of the New Hampshire Association of Realtors, commercial division, were enthusiastically applauding the bill they are supposed to hate.

As New Hampshire goes, so goes the nation, it seems. Interviews with senators who spent the congressional recess talking to constituents back home indicate that the grass-roots feeling about the Senate's tax-revision bill varies from enthusiasm to indifference -- but with little hostile opposition.

"The recess is helping us rather than hurting us," said Senate Finance Committee Chairman Bob Packwood (R-Ore.).

"In these neighborhood parades I was in, the comments I would get from the sidelines, from obviously very middle-income, working-class people, were: 'That's the way to go, senator,' or, 'I like your tax bill.' They obviously knew something about it," he said.

"It's probably got the widest support of any piece of legislation that I've seen in my 5 1/2 years in Congress," said Sen. Mack Mattingly (R-Ga.). "I'm not talking about senators, I'm talking about people."

Whether that support will translate into Senate passage -- and whether it is as strong as some senators maintain -- remains a question. Proponents of the bill fear the measure could "unravel" if amendments begin passing, especially if they are not coupled with tax increases that would keep the plan from losing federal revenue.

Sen. Slade Gorton (R-Wash.), for example, said he will "of course" vote for an amendment to restore the deduction for state and local sales taxes, which the bill would terminate. Washington state, with a 7.9 percent sales tax and no income tax, would be harmed more by such a change than neighboring Oregon, whose high income tax would remain fully deductible and which has no sales tax.

"In my view, there is no rational reason for treating the two [kinds of taxes] differently," Gorton said. "But I found no sentiment to change it at the cost of the bill."

Packwood said Thursday that 31 senators have agreed to oppose all amendments and that a shifting coalition of at least 20 more would help stave off attempts to keep tax breaks the bill targets for elimination or reduction. But it is not clear how firm those commitments are or how long the line will hold if amendments begin to slip through.

When Packwood called Rudman this week, he did not invite the New Hampshire senator to join the "core group," but merely wanted to know what Rudman's constituents were saying and whether he would propose amendments to the bill.

Like other senators polled by Packwood, Rudman has "concerns" about a particular provision -- in his case, doing away with low tax rates on capital gains. Like the others, he does not plan to propose an amendment himself -- but has not ruled out voting for someone else's amendment under the right circumstances.

Almost all said their constituents raised questions about restrictions on Individual Retirement Accounts, which would be limited for workers covered by a company pension plan. Some people mistakenly thought the legislation would abolish IRAs, but others objected to new limitations.

Nonetheless, senators said the objections about Individual Retirement Accounts were less vociferous than they might have imagined.

Gorton said they did not seem to be a "passionate concern." And when Sen. Charles E. Grassley (R-Iowa) asked 40 members of the Eastern Iowa Chapter of the International Financial Planners Association how they felt about the bill during a get-together in Cedar Rapids, 35 said they were for the package, four were neutral and one against, Grassley said.

Sen. Don Nickles (R-Okla.) found less enthusiasm for the bill at a Tulsa meeting of business leaders, where perhaps half of the 200 people said they liked it. Considering that the audience was mostly real estate developers, builders and oil and gas producers, Nickles said, that was not such a bad percentage.

A common trait among constituents, senators said, was lack of concern or knowledge of the bill one way or another. When Rudman threw open the floor to questions after a speech to a small town Chamber of Commerce in Derry, he got queries about the gold standard, the deficit, the Korean War and arms control -- but none about the tax plan.