Ah, "The Bill Factor."

We here at NEWSWEEK started the conversation back in May. New York magazine followed up in October. In between, hacks like me spilled enough ink to fill a special branch of the Library of Congress with essays, editorials, gossip and reporting on what Bill Clinton means for Hillary Clinton's candidacy, what a Hillary White House would mean for Bill--and what Bill and Hillary, together, mean for the future of America.

But no one bothered to check in with the poor folks who'd potentially serve under Hillary--and, presumably, Bill--in second Clinton Administration.

Take, for example, Joe Biden. The press assumes that Biden--like his fellow second-tier candidates, all of whom are polling under five percent--is running not for president but vice president. So reporters ask, over and over, whether he (or Bill Richardson, or Chris Dodd) would accept the second slot. Usually the candidate recites some pabulum like, "No, we're focused on winning right now." But over the weekend, Biden gave CNN a pretty good reason why not. Its name? Bill Clinton. "If I don't win the nomination, the likely nominee is going to be Hillary," he said. "And I love Bill Clinton, but can you imagine being vice president?... I'm not looking for a ceremonial post."

During lunch with NEWSWEEK yesterday, Biden reinforced his refusal to serve as Hillary's veep--and added Secretary of State to the list. But he also left the door open for Obama and Edwards, meaning that it's not the job he doesn't want--it's Bill and Hillary as bosses. "In a Barack administration, in an Edwards administration, I'd probably be looked to a whole lot more," he said. "Now, I don't think they would ask me. But I think they would look to me more. Do you think Hillary's going to call me in the room when she decides what she's going to do?"

I doubt Biden would turn down a top slot; very few ever do. Still--does he have a point? Would Bill, the only former president to reoccupy the White House as a First Spouse, act as Hillary's real second- (and third-, and fourth-) in-command--rendering her vice president and even Secretary of State less powerful than any of their predecessors?

Sorry, Joe. According to the experts, there's not much stopping him.

First off, he's an ex-president. Not only does that trump "senator" in the experience department, but in the last half-century it's become a position of security and power that would've astonished at least the first twenty-four men who outlived their own time in the White House. Ex-presidents are entitled to some form of executive privilege, thanks to Truman's argument in 1953, when called before HUAC, that he could not be forced to testify about his actions while in office (Nixon revived the defense twenty years later). The Former Presidents Act of 1958 declared that ex-presidents were entitled to receive "a monetary allowance" of $25,000 a year (it's now about $180,000), authorized a government-funded staff, provided for office space, furnishing and equipment and granted free mailing privileges. In 1963, the Senate modified its rules to give ex-presidents the right to use the upper chamber of Congress as a forum whenever they wished. After Kennedy's assassination, Congress provided ex-presidents (and their families) with a Secret Service detail. President Johnson put Air Force jets and helicopters at Hoover, Truman and Eisenhower's disposal; the privilege has continued. In 1969, a Victorian townhouse adjacent the White House was deemed the official Former Presidents' Residence. And in recent years, sitting presidents have given their predecessors limited security briefings (printed and/or oral, consisting, says Rutgers professor John Whiteclay Chambers II, of "just as much as the current president wants them to have") and expected them to attend the funerals of foreign leaders as representatives of the United States.

Executive privilege, money, a townhouse, security briefings and access to the Senate, Secret Service and Air Force--not a bad life. But here's where Biden's really buried. Despite all those powers and perks, the quasi-official office of the ex-president pales in comparison to the almost entirely unofficial and unregulated position of First Spouse in terms of access and potential influence.  The job isn't mentioned in the Constitution, and for the first 200 years of the Republic it wasn't subject to any federal statute or law. Even now, the only restriction is on gifts accepted from foreign governments -- i.e., unregulated income that the First Spouse would bring in as a result of being married to an elected official (remember Nancy Reagan?). There are congressional appropriations for first-spousal security and staff--but otherwise, it's all off the books.

The result? Bill's potential influence, unlike Biden's, would be unlimited. "There's no standard for how much information and access a former president receives from the current administration," says Mark K. Updegrove, author of "Second Acts: Presidential Lives and Legacies After the White House" (and former publisher of NEWSWEEK). "But 'pillow talk' absolutely supercedes anything that it could offer on a formal basis."

"The whole status of former president wouldn't even enter into it because a president can tell his spouse anything he or she wants," adds Carl Sferrazza Anthony, author of "First Ladies: The Saga of Presidents' Wives and their Power. "The whole role of First Spouse is the 'Don't ask, don't tell' position in American political culture."

Hear that, Bill Richardson? Never has that "governor of New Mexico" gig looked so good.