Barack Obama may soon join a not-so-exclusive fraternity: current senators running for president in 2008.

By my count, 14 sitting senators have been mentioned as potential candidates, with at least nine likely to run.

As for Obama, he is overrated, almost by definition. It is truly remarkable that a previously unknown figure can serve less than two years as senator and grace the cover of major national magazines, write best-selling books and make journalists drool over his every word. Obama is an overnight rock star, but that status is hard to live up to.

That being said, Obama is a very impressive figure. I heard many speeches on the floor of both conventions in 2004, and his was the most dynamic. He is smart and pragmatic and has stepped into the role of senator in a way that few freshmen do. If he had more seasoning, he would be a natural candidate for 2008.

In politics, however, the future is uncertain. Who is to say whether Obama will be viable in 2012 or 2016? Bill Bradley waited too many cycles to run for president. Eventually the buzz subsides.

The donkey in the room is Hillary Clinton. Obama’s candidacy must take her into account.

Clinton’s strength is enormous, especially compared to her weakness in 2000 when she was the soon-to-be ex-first lady, who had never won her own public office and was discouraged from running for Senate by many fellow Democrats. She was viewed as far to the left of her centrist Democrat husband and was a polarizing figure with high negatives.

Through skill and circumstance, she has turned around most of these negatives. She was elected and will be reelected easily. She quickly became a major presence in the Senate, with respect from both sides of the aisle.  She was a senator from New York on 9-11, which thrust her into the subsequent debates over homeland security and foreign policy. Along the way, she tried to carve out more moderate positions on issues such as abortion, violent video games, and national security. In, 2000, no one would have believed that her chief challenge for the 2008 Democratic nomination would come from her left. But that is what John Kerry and several others will do, with the backing of the anti-war, Net-roots community, which grumbles that Clinton has sold out. In the end, however, Clinton is likely a strong enough presence with an established liberal reputation to beat back such a challenge and go into the general election flush with cash and with a more moderate reputation.

So how could Obama win? First, he could run, hope that Clinton implodes, and emerge as the replacement. But short of implosion, Obama must take on three political personas and merge them into a cohesive whole.

First, do not underestimate the strength of a dynamic African-American leader in the Democratic primary. African-Americans provided nearly one quarter of John Kerry’s vote against George Bush, and Jesse Jackson received the votes of almost one third of the delegates in the 1988 convention.

Second, Obama must excite the anti-war crowd. In his favor, he was not in the Senate to cast a vote for the Iraq War, but his pragmatic persona may not be as suited as Howard Dean’s to capturing this vote.

Third, Obama can run as a “fresh face,” especially since Clinton, Kerry, Gore and even last election’s fresh face, John Edwards, are well worn in the public’s eye.

These three roles will be hard to blend, but if Obama emerges as the fresh faced, African-American, favorite of anti-war crowd, then Hillary Clinton should watch out.

Fortier is a research fellow at the American Enterprise Institute.