DAVENPORT -- There may be no other issue in this presidential election that sets John McCain and Barack Obama farther apart than taxes.

Throughout the campaign, McCain and Obama have aimed fire at one another over how each would treat the government's primary revenue source.

McCain accuses Obama of wanting to raise taxes, thus killing jobs.

Obama says he would, in fact, cut taxes for more middle-income Americans than his rival, and that is what is needed to ignite the country's economy.

Republicans have traditionally run well by stressing tax policy. And there's some evidence McCain's attacks on Obama's plan have hurt. A Gallup poll in August said 53 percent of respondents thought Obama would raise their taxes. Only 34 percent thought that of McCain.

A more recent Washington Post poll, though, said they were nearly dead even when voters were asked which candidate they could trust most on taxes.

Here's an outline of their plans:

McCain, a Republican senator from Arizona, has proposed extending the 2001 and 2003 tax cuts, increasing the exemption for dependents to $7,000, reducing taxes on corporations and setting the estate tax at 15 percent while excluding the first $5 million from taxes. He would also cut corporate taxes from 35 percent to 25 percent.

Obama would extend only selected provisions of the 2001 and 2003 tax cuts, including the expansion of child credits. He also proposes a series of new tax breaks ranging from a credit for working couples, a break for education expenses and elimination of taxes on seniors making less than $50,000.

The biggest difference in their plans is Obama's proposal to let the cuts in the two top tax rates approved in 2001 expire in two years.

McCain would extend them. Three weeks ago in Cedar Rapids, the Republican lampooned the idea of raising taxes in a struggling economy. "It's just plain dumb," McCain said.

Obama complains the McCain camp is distorting his tax plan, and that McCain's push to extend the tax cuts for wealthy Americans is a continuation of President Bush's economic philosophy.

Obama says he would cut taxes on families making less than $250,000.

Only those who are making more would see their taxes go up, he said.

"I will cut taxes -- cut taxes -- for 95 percent of all working families," Obama said in Florida last month.

A study by the nonpartisan Tax Policy Center says Obama's tax plan would cut taxes for families making less than $66,000 -- about 60 percent of taxpayers -- between $550 and $1,000 next year.

McCain's plan would only cut taxes for that group by between $20 and $320, the center says.

Their plans are more similar for the typical family making between $66,000 and $111,000, the center says.

Obama would cut taxes for them by $1,300, McCain by $1,000.

From there, the differences widen and they are particularly stark at the top of the income scale.

For people making $600,000 to $2.9 million, McCain would cut their taxes by more than $45,000.

Obama would raise them by nearly $116,000. Families with incomes of more than $2.9 million a year would pay $700,000 more.

"Basically, Obama would let the tax cuts expire for high-income taxpayers and he uses the extra money to pay for certain targeted tax provisions for low- and some middle-income taxpayers," says Ben Harris, senior research associate at the Tax Policy Center.

McCain's campaign objects to the idea that only wealthy Americans will be hurt by increasing the top rates.

It says small businesses, many of which pay taxes at individual rates, will be hurt, too.

That is the wrong thing to do in a struggling economy, says Douglas Holtz-Eakin, McCain's chief domestic policy adviser. He says businesses with 50 and fewer employers are the ones creating jobs in today's economy.

"Everyone else has gone in the wrong direction," he said. "Now is the wrong time to do this."

Obama's campaign says the complaint is overblown and only a tiny slice of businesses would be effected.

"His plan overall is a balanced approach to cut taxes for middle class families and grow the economy again," said Brian Deese, Obama's deputy economic policy director.

Ed Tibbetts can be contacted at (563) 383-2327 or etibbetts@qctimes.com.