OBAMA FOR PREZ?….Ryan Lizza argues in the New Republic that Barack Obama needs to run for president in 2008. Why? Because in 2012 he’d have to face an incumbent and in 2016 he’d be perilously close to terminal overexposure:

My favorite law of American politics is that candidates have only 14 years to become president. That is their expiration date. The idea was conceived by a very smart political junkie who happens to be a senior aide to Vice President Cheney (don’t hold that against him), and the law was popularized in a column by Jonathan Rauch of National Journal. As Rauch put it, “With only one exception [Lyndon Johnson] since the presidency of Theodore Roosevelt, no one has been elected president who took more than 14 years to climb from his first major elective office to election as either president or vice president.”

As Rauch showed, the majority of presidents since 1900 have fallen on the low end of this zero-to-fourteen-year spectrum: zero (Dwight Eisenhower, Herbert Hoover, William Howard Taft), two years (Woodrow Wilson, Theodore Roosevelt), four years (Franklin Roosevelt, Calvin Coolidge), and six years (George W. Bush, Jimmy Carter, Richard Nixon, Warren Harding). The lesson is that Obama must strike while he is hot or risk fading into obscurity.

This is actually an interesting theory that I’d not heard of before. And yet….it doesn’t sound quite right. The phrase “from his first major elective office to election as either president or vice president” sounds pretty strained to me, as though it were invented solely to make the 14-year point.

Instead, how about taking a broader look at political fame and figuring out how long it usually takes between becoming nationally famous and becoming president? Roughly speaking, that puts Hoover at 11 years (1917-1928), FDR at 12 years (1920-1932), Eisenhower at 10 years (1942-1952), Nixon at 20 years (1948-1968), and Reagan at 16 years (1964-1980). And even by the original measure, LBJ took 20+ years, Kennedy took 14 years, and Clinton took 14 years to become president.

This doesn’t completely defang the theory. After all, Nixon is always the spoiler to any general theory of who can and can’t become president, and aside from him that leaves only Reagan and LBJ as exceptions to the 14-year rule. It does, however, suggest that 2016, when Obama will have been in the public eye for 12 years, is closer to the sweet spot than it is to the upper end of his shelf life.

And there’s another thing to consider: what’s the low end? How many people have become president a mere four years after winning a major office or otherwise bursting onto the national scene? No one recently. Even Jimmy Carter and George Bush Jr. had six years of major office experience behind them when they were elected.

So count me as skeptical that Obama should be thinking of running in 2008. On the other hand, he should be thinking of ditching the Senate as soon as possible. The “baggage of a complicated voting record and the stench of the Beltway” are indeed campaign killers in American politics. Maybe he’d like to move out to California and run for governor in 2010?