I RECENTLY heard a thoughtful case made for converting Social Security into a system including private accounts, based on such progressive criteria as building wealth in the working class, spreading the tax burden into higher tax brackets and guaranteeing minimum payouts. The liberal spouting this dogma: Jim DeMint.

Sen. DeMint acknowledges the oddness of these arguments coming from him. In other company, he can throw around conservative phrases such as “opportunity society” with the best of them, no doubt. But his policy ideas on Social Security far predate the recent rhetoric of the White House.

Some of the building blocks of Sen. DeMint’s view are likely to startle other Senate conservatives:

• He argues that a revamped Social Security featuring private accounts that can be passed down through families is a way to build financial assets among the poor, who pay this tax now but accumulate little for their heirs. “Asset poverty is the biggest problem we have.”

• He would make the investment rate progressive; that is, those with lower incomes would get to put a higher percentage of their taxes into invested accounts.

• Social Security dollars are not guaranteed to recipients now; we’re all at the mercy of the government’s fiscal decisions. He argues that a revamped program with private accounts could be guaranteed. His plan even offers a further guarantee; he would promise those moving money into investment accounts that they would never receive less from Social Security than they would have gotten under the old plan.

Guaranteeing to protect investors from the market’s ups and downs? You sound like a Democrat, senator.

“Mine is the most liberal plan,” he says. “The only chance my plan has is if the Democrats realize they can steal this issue from us.”

Some Republicans will find the list of options he opposes just as radical. He believes that the retirement age cannot be raised further, citing those workers in manual labor who just can’t stay on the assembly line or work site to 70 years old and beyond. (Many other Republicans oppose raising the age for a more basic reason: It’s considered political suicide to so blatantly anger older voters.) He calls “morally wrong” any cut in the benefits people have been led to believe they someday will get.

Given these views, Sen. DeMint seems well-positioned, if a bit of an odd choice, to bring some Democrats and uneasy Republicans onto the side of private accounts in Social Security. He can argue for his plan on conservative principles to the like-minded, and in more progressive terms to others. During his House tenure he worked hard, and made progress, to get Democrats to take his ideas seriously.

That makes his views something the White House should seize upon, right? After all, a Social Security bill must pass the Senate before it can get to the president’s desk. There are still enough Democrats, not to mention edgy Republicans, to muster up more than 40 votes to filibuster the plan — and the Democrats, on a core issue such as Social Security, will be energized enough to tough it out together, if it comes to that.

But the early signs from the White House do not look good for a compromise.

The administration has sent up a trial balloon on changing the way benefit increases are calculated. The change would make a big dent in the program’s shortfall — but would be, undeniably, a sizable cut in future benefits. Sen. DeMint opposes such a cut, but he says he believes the White House is encouraged by the early response. The White House also might move away from Sen. DeMint on other parts of the legislation that differ from doctrinaire conservatism.

Why would the White House take such a confrontational angle on the president’s biggest domestic priority in his second term? Post-victory arrogance, for one reason. If it doesn’t try to pick up votes from the political center, it is because administration leaders believe they do not need them and can steamroll the plan through anyway. The president would be daring the Democrats to clobber him with the benefit cut.

The second reason the administration might not move to the center: the House Republican caucus. It pays no heed to moderates in its own chamber, and will be disinclined to shift to accommodate centrist senators.

Sen. DeMint, who has worked hard on this issue for years, says he does not fear being stuck by the White House with a Social Security plan he can’t get behind. But so far, the freshman senator and the president are not on the same page on several major points.

Sen. DeMint could get pinned between a Social Security bill he does not like and the president with whom he allied himself so closely during the election — an uncomfortable place to begin his first term.

Write to Mr. Fitts by e-mail at mfitts@thestate.com.