The first weeks of April are the traditional time for presidential candidates to offer their ideas on reforming the tax code, and this year is no different: John Edwards is suggesting that the Internal Revenue Service prepare tax returns for 50 million Americans who have simple tax circumstances.

The former North Carolina senator laid out the idea in an audio podcast posted on his Web site April 7. For Americans whose employers and financial institutions send all of their relevant tax data to the government, the IRS would calculate their bills and mail them completed returns, which he called “Form 1.” Filers could sign the form and return it, or reject it and file their own return if they disagreed with anything in the IRS’s calculations. Form 1 would not be an option for taxpayers with more complicated returns. “Hardworking families who pay their taxes shouldn’t have to pay tax preparers, too,” Mr. Edwards said in the podcast. “With Form 1, there is only one thing you have to do — sign and return it.”

A professor of economics at the University of Chicago, Austan Goolsbee, calculated in a July 2006 report for the Brookings Institution that about 52 million Americans could benefit from a “simple return” idea, a number that includes those whose financial information is in the possession of the IRS and those eligible for a payment to the working poor called the Earned Income Tax Credit.

Mr. Edwards noted that his plan is largely based on a California state version called “ReadyReturn.” But the test run of ReadyReturn offers some interesting lessons for a federal version. The first question is how many eligible taxpayers would use the new service. In 2005, ReadyReturn was sent to 50,000 single taxpayers who had no dependents and only wage income, and it used data that employers already reported to the state. Overall, more than 11,000 people used ReadyReturn. Mr. Goolsbee noted that 22% of the people who declined said they had already filed their tax return when they got the mailing.

Staunch opposition from existing tax preparers represented another significant hurdle. A group of ReadyReturn opponents — including the California Chamber of Commerce, the California Taxpayers’ Association, and the Computer & Communications Industry Association — mobilized to sway state legislators. The Mountain View, Calif.-based creator of the Turbo-Tax tax preparation software, Intuit, was particularly active in lobbying against the new program.

At the delightfully unsubtle URL taxthreat.com, the ReadyReturn opponents touted a poll that found that 67% of respondents opposed the program, that 7% of respondents trusted a state agency to prepare their taxes, and that 81% preferred “an independent tax preparer.”

The Legislature only approved ReadyReturn for two years, and the program will not be available to California taxpayers this year. But in December, the state’s Franchise Tax Board voted to restart the program in 2008 and expand it to 1 million eligible taxpayers with simple tax returns. Intuit has threatened legal action, contending the state board is stepping into the Legislature’s duties.

Mr. Edwards’s campaign is aware of the staunch opposition from tax software firms, promoting its idea as an example of “taking on special interests.”

Beyond the bumpy road of ReadyReturn, Mr. Edwards’s tax simplification proposal may face opposition, or at least a lack of enthusiasm, because it simplifies the tax filing process only for those who spend the least amount of time and effort on it already.

Because the IRS can only prepare tax forms for those with the simplest of tax circumstances, under Mr. Edwards’s plan the agency would essentially be doing the work for those who currently file the 1040EZ form.

Mr. Edwards’s release cited an oft-mentioned statistic from the IRS: “It takes seven hours to complete even the simplest tax form, the 1040EZ.” Yet the figure is a head-scratcher: The 1040 EZ is two sides of a one-page document, and the process of completing the form is 13 steps at maximum; for most filers, several steps could be skipped, such as calculating unemployment compensation.