WASHINGTON — The chairman of the House Ways and Means Committee, Rep. Charles Rangel, said a proposal to curtail the alternative minimum tax and boost taxes on buyout firms will have benefits for so many people that it may pass the Congress with enough votes to override a presidential veto.

The fix to the AMT will be combined with increases in the earned income and child tax credits so that about 90 million people could benefit from the final proposal, Mr. Rangel said in an interview Wednesday. He earlier said he plans to combine the AMT with a proposal to more than double taxes on carried interest — the compensation that investment managers at hedge funds and private equity firms earn.

“When you begin to see how many people in the U.S. would enjoy the benefits of a tax reduction, this might be a veto-proof bill,” Mr. Rangel, a Democrat of New York, said

Combining the carried-interest tax boost with a cut in taxes for middle-class families may make it difficult for Republicans to vote against the plan. President Bush said he’s opposed to the carried-interest bill.

Mr. Rangel said his committee would hold hearings in September on a variety of tax proposals with an eye toward “putting more equity into the system.” He said the committee would “take a look at the upper rate to see if there can be a more equitable distribution of the tax” and pledged not to eliminate incentives for investment.

Mr. Rangel is a co-sponsor of legislation proposed by Rep. Sander Levin, a Democrat of Michigan, that would tax the share of profits that managers receive in exchange for investment services as wages at rates as high as 37.9%. That income, known as carried interest, is currently taxed at the 15% capital-gains rate.

The revenue from that measure would generate only a small portion of the revenue needed to pay for overhauling the alternative minimum tax under pay-as-you-go budgeting rules adopted by Democrats earlier this year. Unless Congress acts, the AMT will impose a $45 billion tax increase on 23 million households in 2007.

In the Senate, the Finance Committee has held two hearings on the issue. The Finance Committee chairman, Senator Baucus, a Democrat of Montana, and Senator Grassley of Iowa, the top Republican on the panel, say they’re considering drafting their own legislation. Senator Schumer, a Democrat of New York, said he’ll introduce a bill to boost carried-interest tax in all partnerships rather than exclusively on investment firms.

Messrs. Baucus and Grassley previously introduced legislation that would make buyout and hedge-fund firms that go public pay taxes as corporations at rates as high as 35%. Under the current system, partners in these firms pay taxes at individual rates as low as 15%.

Mr. Grassley said he expects that bill to be combined with an AMT fix in the Senate.