Are your taxes fair? Increasingly, Americans say no.

This April 15, fewer Americans feel their tax bills are fair, while Republicans and the White House are continuing their battle over the merits of federal spending.

A new Gallup poll found that 55 percent of Americans think the federal income taxes they pay are fair. This is the lowest fairness grade the polling firm has found since 2001, and it's down from the 59 percent who said their tax bills were fair in 2012. But the decline from last year, while part of a general downward trend since 2003, is within the poll’s margin of error of plus or minus 4 percent.

Income level does not affect whether a person sees his or her taxes as fair, Gallup analyst Jeffrey Jones wrote. “The biggest differences are based on political affiliation, with Democrats and political liberals much more likely than Republicans and conservatives to believe their taxes were fair,” Mr. Jones said. For the current tax year, 70 percent of liberals, 59 percent of moderates, and 45 percent of conservatives believed the taxes they paid were fair.

On Monday, both sides in the ideological battle sought to reinforce the divide by presenting their cases on tax-funded spending. House Speaker John Boehner’s office posted a video of the speaker standing next to a “red tape tower” of regulations that's 20,000 pages high and seven feet tall. The tax code amounts to four such towers, he said. 

“Our tax code is a headache for families and workers, and it’s a nightmare for small business owners,” Mr. Boehner said. “That is why Republicans want to fix it.”

A more aggressive tax day message came from the National Republican Congressional Committee, which is charged with keeping the House in Republican hands in 2014. NRCC rapid response director Matt Gorman wrote, “As Americans file their taxes, Barack Obama, Nancy Pelosi, and their liberal allies are already writing their wasteful spending wish lists full of robo-squirrels, climate change musicals, and NASA video games.” The items Mr. Gorman cited were included in the “Wastebook 2012” from Sen. Tom Coburn (R) of Oklahoma.

To counter Republican charges that tax dollars are routinely spent on projects like a $697,000 musical on climate change and biodiversity, the White House rolled out an updated version of its federal taxpayer receipt on an interactive website. The website lets visitors enter their own personal tax payments, and it provides detailed information for several income levels and personal situations.

For example, it shows where the federal government spends the tax dollars provided by a married couple with an income of $80,000 and two children. It says the family would have paid more in Social Security taxes – $4,960 – than in federal income taxes – $3,863. Of their total income tax payment, the biggest share – about $1,015 – would go to national defense. The next-largest share would go toward providing health care, with interest on the federal debt accounting for about $285 or 7.4 percent of the tax payment.    

The goal of the taxpayer receipt application is to defend Mr. Obama’s economic policies. “The President believes the economy grows best from the middle out, not from the top down. That’s why he fought to make the middle class income tax cuts permanent. Additionally, millions of folks continue to be able to take advantage of things like the American Opportunity Tax Credit, and the expansions to the Earned Income Tax Credit and the Child Tax Credit,” wrote Colleen Curtis, director of digital content at the White House, in a blog post accompanying the taxpayer receipt.

Views on tax fairness are affected by events affecting the nation’s welfare. As Gallup notes, during World War II, few Americans complained about the fairness of their tax payments. Between 1943 and 1947, an average of 87 percent of Americans said their taxes were fair. The public's view of the fairness question improved from 51 percent in 2001 to 58 percent in 2002, after the Bush administration pushed for passage of a round of tax cuts, Gallup notes. 

When it comes to deciding whether other people’s taxes are fair, Americans “have mixed views on whether the poor and middle class pay their fair share in taxes,” according to a Pew Research Center survey. One area of consensus was that a majority of adults (58 percent) said that upper-income people pay too little in federal taxes. One in 4 (26 percent) said upper-income people pay their fair share in taxes, and 8 percent said they pay too much in taxes, Pew found in the 2012 survey.