With New Yorkers facing the second highest total tax burden after Connecticut, according to the nonpartisan Tax Foundation, the tax returns we file on Monday are very much on the minds of many of us this weekend. Taxes are also on the minds of the politicians who are already running hard for the presidency.

Election Day 2008 is 19 months away, but the presidential candidates, with uncommon specificity this early, are setting forth widely different views and values about how the federal tax system should be changed.

Most of the Bush tax cuts of 2001, 2002, and 2003 expire in 2010. To the extent that happens, the higher rates would raise additional federal revenue.

How much extra revenue would Congress get if and when the current levels of taxes rise? The Congressional Budget Office estimates that all the expiring tax cuts, if allowed to lapse, would increase revenues by $374 billion over the 5-year period beginning in 2008.

The largest component of the tax increases would be from the individual income tax rate cuts of 2001, which reduced tax rates at the low end to 10% from 15%, and at the high end to 35% from 40%. Reversion to the 2000 rates would bring in $267 billion of the total $374 billion over the period between 2008 and 2012.

Allowing the estate tax to return to its pre-2001 level would bring in another $102 billion to Uncle Sam in 2008-12. Eliminating reduced rates on dividends and capital gains would raise $32 billion. Small businesses would pay another $12 billion if favorable investment incentives expired.

Democratic candidates such as Senators Clinton and Obama want to devote additional revenue to lowering or eliminating the alternative minimum tax. The AMT is a type of flat tax of 26% or 28% from the 1960s that was originally designed to prevent tax shelters for the very rich. Because it is not indexed for inflation, and with incomes rising, more and more taxpayers have to pay the tax.

According to the Urban Institute-Brookings Institution Tax Policy Center, the AMT will affect 3.5 million filers filing their 2006 returns on Monday. These are chiefly families with large numbers of children in states with high income taxes, such as New York, all of which reduces their taxable income and makes them subject to the AMT.

Increased exemption levels for the alternative minimum tax expired at the end of 2006, and, if nothing is done, about 23 million tax filers for the 2007 tax year could be subject to the AMT. To restore the exemption levels that were in effect last year would cost the Treasury $250 billion in 2008-12, plus $9 billion for 2007, a high percent of the revenue that will flow in if the Bush tax cuts are not extended.

Senator Clinton declared on March 14, “I’ll tell you something else that we are going to have to deal with, the alternative minimum tax, which falls heavily on a lot of you and your families. … with all due respect, do the billionaires in America need more tax cuts? Don’t you think we ought to cut the taxes of middle income people, in particular those who are going to be hit by the alternative minimum tax?”

All leading Republican presidential candidates favor making permanent the Bush tax cuts. In order to pay for them, they vie with each other for the title of “most fiscally conservative.”

Governor Romney goes beyond extending the Bush tax cuts. He also calls for further cuts in marginal tax rates, as well as an exemption from tax on dividends and capital gains for middle class Americans. He would cut the AMT a year at a time, to allow flexibility to keep other taxes low.

In order to pay for the tax cuts, Governor Romney would limit the growth of nondefense discretionary spending to 1% lower than the inflation rate. That means that if the inflation rate is 2%, he would keep nondefense discretionary spending at 1%. He calculates that this alone would save $300 billion over 10 years.

In a speech to the Club for Growth in Florida on March 29, Governor Romney said, “If spending exceeds this threshold, I will veto appropriations bills. If you don’t believe me, look at what I did in Massachusetts, where I vetoed hundreds of bills sent to me by the Democratic legislature. I know how to veto. I like vetoes.”

Rudy Giuliani also claims the mantle of the most fiscally tough candidate. He has not released specific tax proposals, but his Web site states that “Rudy is the real fiscal conservative in the race. He cut taxes 23 times in New York and turned a $2.3 billion budget deficit into a multi-billion dollar surplus. … Rudy Giuliani believes in supply-side economics, because he did it and he saw it work.”

And Senator McCain would like to make the Bush tax cuts permanent and reform the estate tax in as yet unspecified ways. On his Web site he writes that “… tax cuts work best when accompanied by lower spending. Higher taxes and greater spending discourage entrepreneurship, foster wasteful tax-planning and slow long-term growth.”

As April 17 approaches, New Yorkers need to be mindful of the taxes they pay this year, and of how taxes can rise in the future if Congress does nothing. With politicians now considering how to allocate billions of tax dollars that might fall into the federal coffers in 2010, these are dangerous times.

Ms. Furchtgott-Roth, former chief economist at the U.S. Department of Labor, is a senior fellow at the Hudson Institute.