The retirement savings plan that federal employees enjoy and President Bush cites as a model for his individual investment accounts differs in a key regard from what he proposes: Bush would carve the new accounts out of the Social Security taxes workers now pay.

The government workers' savings plan, by contrast, is in addition to the Social Security taxes they pay and the benefits they are promised.

Democrats have said they would be much more inclined to embrace the private accounts - the signature item of the president's proposed Social Security overhaul - if they, too, were treated as an add-on to the traditional benefit check rather than a partial replacement.

One Republican, Rep. Clay Shaw of Florida, who oversees a House Social Security subcommittee, has filed legislation that would create the accounts as an addition to the program. But so far the broader debate over ensuring Social Security's long-term solvency has stalled over opposition to the president's "carve-out" accounts.

"It is just so unfair, misleading and fraudulent," Senate Minority Leader Harry Reid said of the president's references to the Thrift Savings Plan. The Nevada Democrat accused the administration of using carve-out accounts as a Trojan Horse for eliminating Social Security, by siphoning off the taxes that pay benefits.

Rep. Steny Hoyer of Maryland, the No. 2 Democrat in the House, said: "It's a political pitch because his accounts can't stand on their own merits, so what he tries to do is pretend that the Thrift Savings Plan that Congress and federal employees have is the same as what he's proposing and is something Congress is denying to the public."

Trent Duffy, a White House spokesman, said the president does not highlight the Thrift Savings Plan because of the way it is funded but because of the investment options and risk management it affords.

"The president talks about the TSP in the context of a safeguard approach," Duffy said. "And, conceptually, it is the same thing if you - voluntarily - are given the option to set aside funds in a limited amount of investment options that might get a better return over a set period of time."

Federal employees, including members of Congress, currently have a retirement program that is the model of what most investment advisers suggest for any worker. Advisers liken it to a three-legged stool.

The employees pay into Social Security, qualifying them for a government retirement check. A portion of their pay also goes into a pension program, the Federal Employees' Retirement System, which pays a benefit based on their tenure. And they have the option to participate in a so-called defined contribution program, the Thrift Savings Program.

Like a private-sector 401(k), it allows workers to make contributions - a portion of which the government matches - that can be invested five different ways, including government and corporate bond funds, as well as a stock fund that tracks the S&P 500.

The stock funds performed well in the 1990s, with annual returns over 37 percent one year. But in the aftermath of the 2001 recession, they have posted annual losses as high as 22 percent. Over the most recent 10-year period, all the funds were profitable, according to the plan's Web site.

The private accounts the president has proposed for younger workers would be funded with up to 4 percentage points of the 12.4 percent payroll tax they now pay into Social Security.

On the stump, Bush does not mention the different manner in which the Thrift Savings Program is funded, only the example it should provide in the current Social Security debate.

"Doesn't it make sense for members of Congress to give younger workers the opportunity to do the same thing with their money that they get to do in their retirement system?" he asked Wednesday in Cedar Rapids, Iowa, baiting his congressional opponents. "Frankly, if it's good enough for federal workers and elected officials - putting aside some of your own money in a personal savings account - it ought to be good enough for all workers in America."