Hillary Clinton’s now infamous Martin Luther King Day comparison of Congress to a plantation has resuscitated many centrist Democrats’ concern that their early front runner for 2008 may not be made of the same stuff as her husband.

Bill Clinton was christened “The Natural” by Time magazine’s Joe Klein in a biography of the same name. He was a political thoroughbred, energetic and brilliant if undisciplined, possessing intuitive emotional intelligence. He was always able to connect with his audience, sometimes against their own better judgment. Clinton left office with a 60% job approval rating even after his impeachment.

It’s a cliche to say that opposites attract and that politics makes strange bedfellows. But in the case of the Clintons, both may be true, because if Bill Clinton is The Natural, Hillary Clinton is The Professional.

Once a Goldwater girl from the Chicago suburbs, Hillary is the prototypical good student – undeniably successful and highly disciplined, but with a cold intelligence more evident than emotional intelligence. Her studious attempts at centering her image in the Senate – by endorsing a Bush-lite position on the war in Iraq and sponsoring a bill to outlaw flag burning – have not convinced voters to reassess their fundamental perception of her as a liberal who is smart and hard-working but opportunistic; an expert in strategy but not empathy.

Bill Clinton loved the minutia of campaigning; even keeping a collection of campaign buttons near his desk in the Oval Office. He seemed to gain energy from the crowds, once explaining that what he loved about running for office was that “you get to hear about another life story. It’s like being able to peel another layer off an unlimited onion every day.”

But while her husband seemed to gain energy from a rope line, Hillary Clinton seems to regard it as a necessary indignity on the way to wielding power and influence. Even while she intensely focuses on the person at hand, you get the sense she’s looking forward to washing with Purell. She feels purposeful about helping “people” in the abstract, but seems uncomfortable with the inherent messiness of individuals.

The essence of her husband’s political success was his ability to reach out beyond his party’s base, re-connecting with moderates and the middle class. Bill Clinton understood that no Democratic candidate for president except FDR and Lyndon Johnson had received more than 51% of the vote in the past 100 years. To overcome that deficit, successful Democrats depend on winning over moderate Republicans and independents. He received crucial support in 1992 from Republicans for Clinton-Gore clubs which sprang up in swing states such as New Jersey. It is almost impossible to image Republicans for Hillary clubs emerging on anything other than campaign stationary.

Hillary Clinton is a polarizing figure even within the Democratic Party. She is instinctively opposed by moderate Republicans and Independents. The problem is not political, it is personal. Her Senate voting record might reflect all the right moves, but as her comments on Martin Luther King Day indicate, she is not above pandering by playing the race card, confirming many Americans’ worst concerns about the left wing of the Democratic Party.

In an attempt to stop the cash-driven coronation, increasingly nervous centrist Democrats are taking a look at a new crop of genuine new Democrats more in the mold of Hillary Clinton’s husband than herself. Chief among these at the moment is a former governor of Virginia, Mark Warner, a successful entrepreneur who received astronomical approval ratings running a red state as a New Democrat. Perhaps most impressively, he was succeeded by his lieutenant governor this past fall. If Republicans lose Virginia’s 13 electoral votes in 2008, they would be extremely difficult to make up elsewhere on the map.

Senator Evan Bayh of Indiana has been charged by some critics as being charisma deficient, but as chairman of the centrist Democratic Leadership Council and popular former governor, he appears to be a classic red state family man, precisely the kind of figure his party has lost in the recent past.

There is also Governor Bill Richardson, of New Mexico a former congressman and United Nations ambassador. Mr. Richardson may be able to help Democrats break through in the southwest, while also reclaiming the significant incursions into the Hispanic vote made by George W. Bush.

So far, Hillary appears to be hurtling toward an easy re-election to the Senate this year, but a new poll by Diageo/Hotline released on January 20 confirms many of her weaknesses as a presidential candidate. It showed Senator McCain beating her in a head-to-head match up by 52% to 36% – an electoral landslide along the lines of Ronald Reagan in 1980. The strength of that match up stems directly from Mr. McCain’s credentials as a leading centrist Republican with ability to appeal to centrist Democrats and Independents as well as Republicans.

But before Republicans grow over-confident, a little noticed statistic buried in the same poll showed Hillary Clinton narrowly defeating a generic Republican in a head-to-head race. What this means is that she can beat an uncharismatic social conservative. That should be a wake up call to those who buy wholeheartedly into the play-to-the-base strategy.

Hillary Clinton is a consummate political professional and cannot be counted out in 2008. But the differences between The Natural and The Professional in the presidency would be even more pronounced. With Hillary Clinton in the White House, the biggest problem might not be policy but deeper political polarization – and that is what our country can least afford.