Topeka ? A proposed cut in the state’s top corporate income tax rate and other changes in business tax laws won the endorsement Friday of the House Taxation Committee.

House leaders don’t know how much revenue the state would lose because of the proposed changes. But they believe it will be at least $20 million after four years, when all the changes are phased in.

The relief is aimed primarily at Kansas businesses, but some out-of-state businesses would have their taxes reduced. However, others would pay higher taxes because the bill would eliminate what some lawmakers see as loopholes.

Supporters view the bill as an economic stimulus measure. The tax rate businesses pay on profits exceeding $50,000 would drop to 6.85 percent from 7.35 percent.

“We’re trying to make the business climate better in Kansas,” House Speaker Melvin Neufeld, R-Ingalls, said in a news conference following the committee’s meeting. “We need to have our tax policy so that we can try to attract more businesses.”

The committee’s endorsement, on a voice vote, sent the bill to the House for debate. But the action didn’t come without criticism.

Rep. Nile Dillmore derided the bill as a “Christmas tree” that became unnecessarily complex. He said many legislators, business leaders and the Department of Revenue had agreed on closing some loopholes in exchange for dropping the top tax rate even lower, to 6.35 percent.

He also said the bill would create budget problems. He said the original goal was to prevent a net loss of state revenues by balancing any cuts for Kansas businesses with higher taxes for some out-of-state firms.

“We’ve gone too far,” the Wichita Democrat said. “We’ve lost sight of what it was we were trying to do in the first place.”

There also may be questions from Americans for Prosperity, which advocates lowering taxes and controlling the growth in government spending.

Alan Cobb, the group’s state director, said it will have to study the bill, but added, “Generally I think that the tax code shouldn’t pick winners and losers.”

“We should lower the tax burden for everyone,” Cobb said.

The bill would rewrite rules covering some interest income and income from transactions outside a company’s normal activities, such as when a retail chain sells some of its property. Critics say some large, out-of-state companies escape taxes when Kansans firms pay them.

Those changes would raise $22.5 million annually.

Offsetting those changes would be the cut in the top corporate income tax rate and a new sales tax exemption, starting July 1, 2009, for the equipment that businesses purchase for research and development, a proposal from Gov. Kathleen Sebelius.

Also, the bill would phase in over four years a sales tax exemption on equipment purchased by telecommunications companies.

And it would rewrite the rules dealing with an income tax credit that companies receive for adding high-paying jobs in Kansas.

It would allow a parent company to transfer the credit among its subsidiaries, so that it would benefit even if the subsidiary creating the Kansas jobs didn’t generate any income.