"The governor's proposal will take an unfair tax system and make it more unfair," Matthew Gardner, the institute's executive director, said during an interview.

But the group's analysis also shows that all classes of taxpayers â¿¿ from the bottom 20 percent earning less than $20,000 to the top 1 percent earning $439,000 or more â¿¿ would see at least a small income tax cut. Jordan has said all income taxpayers would benefit. The institute's analysis "confirms what we've been telling people all along," he said in a statement before the hearings.

Even some Republicans have been wary of eliminating the tax relief for homeowners because more than 300,000 filers claim property tax deductions and about the same number claim deductions on home mortgage interest. Brownback's administration estimates that ending the deductions will raise $231 million during the fiscal year beginning in July, but the Washington institute believes that estimate is overly optimistic.

Jordan said the governor is being "pragmatic" as he pursues his goal of eliminating income taxes, adding, "I think the governor and everybody's willing to meet with anybody who has a different idea."

The institute said that while the poorest taxpayers would see their income taxes drop slightly under Brownback's plan, the sales tax change would more than offset it, boosting their overall tax burden by $22 a year, which equals two-tenths of 1 percent of the average income for people earning less than $20,000. Meanwhile, even with the sales tax provision, the top 1 percent will save on average more than $6,500 a year, which equals six-tenths of 1 percent of their income.

"It's another round of pretty meaningful tax cuts at the top," Gardner said.

Last week, Jordan met with reporters to bolster the administration's case that further cuts in individual income tax rates would more than offset the loss of the deductions for homeowners. He had examples from four counties.

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