The release of the proposals launched into motion a frantic political effort that could impact almost every American. In a number of cases, the tax plan cuts back on tax benefits for families and individuals while expanding tax benefits for companies.

The Tax Cuts and Jobs Act would lower the corporate tax rate from 35 percent to 20 percent and collapse the seven tax brackets paid by families and individuals down to four. It could create giant new benefits for the wealthy, cutting business taxes, eliminating the estate tax, and ending the alternative minimum tax.

It would also jettison numerous tax breaks that Americans and businesses have used for years to limit their taxable income.

It would cut in half the popular mortgage interest deduction used by millions of American homeowners, capping this tax deduction at new mortgages of $500,000 or less. Presently, Americans can deduct interest on mortgages of up to $1 million from their income.

This change could have a particularly big impact on high cost areas, such as San Francisco, New York, Boston, and the Washington D.C. area, and housing groups and lawmakers will likely try to defeat it. The bill would allow people to deduct their local property taxes from their taxable income, though this benefit would be capped at $10,000.

The bill’s true impact on the middle class will be difficult to immediately measure. The bill would create a new “Family Credit” and expand the child tax credit used by working families. The child tax credit would grow from $1,000 per child to $1,600 for each child.

The bill would nearly double the standard deduction that many Americans claim on their taxes, raising it from $12,700 to $24,000 per family. But this benefit would be partially offset by the personal exemption many Americans can claim, which can be large for families with multiple children.

Families would also no longer be able to deduct their state income taxes from their federal taxable income, another change that would have a particular impact on places like New Jersey and New York, where state taxes are higher than in other areas.

And Americans would no longer be able to deduct their medical expenses or property and casualty losses, according to a document outlining the plan.

The legislative fight over the tax bill has become the Trump administration’s biggest political goal, after failed attempts to repeal the Affordable Care Act. President Donald Trump wants the legislation to pass the House and the Senate by the end of the year, though they must resolve numerous differences.

The bill would add $1.5 trillion to the debt over 10 years, but Republicans believe the changes would trigger a surge in economic growth, higher wages, and job creation.

Other changes in the bill would be far reaching. It would, for example, make changes to college savings programs and have new requirements for tax-exempt organizations like churches and charities.