"The way I see it," Al Franken told reporters at his first press conference after officially winning Minnesota's endless Senate race, "I'm not going to Washington to be the 60th Democratic senator. I'm going to Washington to be the second senator from Minnesota." It was the politically correct thing to say, of course. Nobody says he's going to Washington to represent a partisan interest or to be a loyal vote for the White House, and everyone emphasizes their desire to help out the local community. Back in the real world, however, just about everyone expects Franken to be a pretty darn loyal Democrat and supporter of the Obama administration position. Still, Franken's correct to downplay the idea that he'll be a 60th Democratic senator. Not so much because his real responsibility is to the people of Minnesota as because it's far from clear that Franken will be joined in Washington by 59 other Democrats.

Even with Al Franken in the Senate, legislative outcomes are overwhelmingly likely to be a fairly pale shadow of the agenda a majority of the public voted for last year.

Most practically, Ted Kennedy (D-MA) and Robert Byrd (D-WV) are both suffering from serious medical problems and are not generally available in Washington to do their jobs. In a pinch, it'll probably be possible to produce them to cast a vote, but one can't quite say for sure.

The larger issue, however, is simply that nothing magical happens at 60. When the president's party reaches 50 senators, it gets to use the vice president's tie-breaking vote to obtain a majority. The bare fact of a majority has consequences. Your party's leader gets to be majority leader, which carries with it the right to set the Senate's schedule. Your party's most senior members get to chair the committees on which they sit, controlling their schedules and a majority of the staff positions. A 50-50 Senate is always a dicey proposition, but there are distinct benefits to being in the majority even if the majority is razor thin.

The 60-vote threshold, by contrast, is important because that's how many votes it takes to break a filibuster. But while the Democratic caucus presumably could get together and collectively commit to refrain from joining any filibusters, there's no sign that they actually will. This means that to move legislation in the modern era, the majority party still needs to painstakingly assemble 60 votes. And it's going to be a difficult task.

For example, considerably more people live in the Bronx than live in Montana. But while the Bronx's 1.4 million people need to share Chuck Schumer and Kristen Gillibrand with 18 million other residents of the Empire State, Montana's cozy crew of 960,000 people has Max Baucus all to themselves. And not only does Baucus' vote count as much as Schumer's or Gillibrand's, he actually has dramatically more power than the senators from New York (or, for that matter, California) because as chairman of the Senate Finance Committee, all health-care legislation absolutely must meet with his approval. The fact that Obama only secured the support of 47 percent of Montana's voters is the kind of thing that must weigh on Baucus' mind. Similarly with Budget Committee Chairman Kent Conrad and Obama's 45 percent of North Dakota's 641,000 residents.

Nor are Baucus and Conrad alone. Byron Dorgan, Jon Tester, Mark Pryor, Blanche Lincoln, Mary Landrieu, Tim Johnson, Mark Begich, Claire McCaskill, and Ben Nelson are all representing states that went for John McCain last fall. Collectively, the states represented by these fine ladies and gentlemen contain about as many people as New York, but their votes are the difference between a majority and a filibuster-breaking supermajority. Meanwhile, among the senators representing states Obama did carry, several—but most notably Indiana's Evan Bayh—have made no bones about their willingness to defy the president and the party leadership on key votes. And of course Connecticut's Joe Lieberman went so far as to endorse McCain in the election and is now opposing a key element of Obama's health-reform agenda.

In many respects the main significance of Franken's victory isn't that it brings us to 60 senators, it's that it increases by one the number of serious progressives in the Senate. But Franken or no, the balance of power still rests with a large block of centrist Democrats and Susan Collins and Olympia Snowe on the other side. The situation by no means dooms Obama's agenda to defeat, but it does mean that legislative outcomes are overwhelmingly likely to be a fairly pale shadow of the agenda a majority of the public voted for last year.

In practice, a big question becomes how much influence can Obama exert over the fairly large number of Republicans who represent states he won. Throughout the Bush years, "red state" Democrats often seemed afraid of standing up to the White House. But what about Republicans like Collins, Snowe, Judd Gregg, Richard Burr, George Voinovich, Mel Martinez, Chuck Grassley, and Richard Lugar, all of whom represent Obama states? Thus far with the very partial exception of Collins and Snowe, this group has offered essentially lockstep opposition to Democratic initiatives. If that dynamic were changed, then the overall legislative landscape could look very difficult. With some Republicans looking to cut deals, then moderate Democrats would need to worry about getting cut out of deals, giving them an incentive of their own to play ball. More generally, once the belief generally exists that a given piece of legislation is going to pass, members of Congress tend to get on the bandwagon, if only to ensure that they play a role in shaping the final result.

But so far, it's not happening. And as long as that pattern holds up, Al Franken’s 60th vote may not be worth very much.

Matthew Yglesias is a fellow at the Center for American Progress Action Fund. He is the author of Heads in the Sand: How the Republicans Screw Up Foreign Policy and Foreign Policy Screws Up the Democrats.