WASHINGTON — Three differences and three similarities will define the contest between Hillary Rodham Clinton and Barack Obama.

The most important difference lies in where their respective political journeys began. After her early work as an advocate for children, Clinton came to political maturity in the South as part of her husband’s efforts to rescue the Democratic Party from its low point in the 1980s. She was shaped by her party’s need to win back moderate and conservative voters who had strayed to Ronald Reagan’s banner.

The resulting Clinton project was a brilliant top-down effort to shape new Democratic ideas that would appeal to Southern whites and the Northern working class. This explains why both Clintons were drawn to the centrist Democratic Leadership Council, far more an elite policy shop than a grass-roots organization.

In a 2002 speech, Clinton signaled her respect for this approach by praising Al From, the DLC’s founder and chief executive, for understanding “from the very beginning … that the right ideas were more important even than improving technology, organization or fundraising.” Both Clintons have employed Mark Penn, the premier DLC pollster, who is incessant in his efforts to locate the political center.

Obama, by contrast, began his political life as a community organizer in inner-city Chicago. His earliest experiences were of a bottom-up politics mobilizing the poor and the marginalized. This had the paradoxical effect of giving some of his ideas a decidedly progressive and activist tilt and others a more conservative tinge.

Consider two statements he made in 1997, shortly after his election to the Illinois Senate. On the one hand, Obama noted that welfare recipients “generally are not represented down here in Springfield,” the capital, and that his job was to stand up for them. But the organizer’s emphasis on local and community responsibility sounded quite traditional when he declared the same year that “though we may be lobbying for more school funding, it’s also important for us to bring education into the homes and ensure parents are checking children’s homework, turning off the television, teaching common courtesy.”

In keeping with his grass-roots background, Obama’s campaign for the 2008 Democratic presidential nomination kicked off with a sense that it was a national movement, while Clinton, from the moment she announced her intentions on Saturday, commanded a well-established, well-staffed and well-financed national organization.

This second contrast can be exaggerated, since Obama will have ample financing. But the feel of the two campaigns is palpably different, with Obama enjoying an advantage on passion and Clinton on organization and discipline.

There are warnings for both candidates from the 1984 Democratic primaries, when Walter Mondale, the clear favorite, was nearly upended by a bright young upstart, Gary Hart. The danger for Clinton is that her front-running campaign will develop the habits of a cautious, inflexible behemoth. The bad news for Obama is that the solid Mondale had staying power and ultimately prevailed, though he lost in November.

There are, however, limits to the 1984 comparison, as a Clinton supporter noted over the weekend. Obama has been built up into a party savior a full year before the primaries — he will not enjoy Hart’s element of surprise — even as expectations for Clinton have been defined downward by the incessant speculation about whether she can win.

Thus the third difference: Clinton, more than any other Democrat, has been both scarred and toughened by the partisan warfare of the past 15 years, while Obama is unscathed and untested.

This contrast was reflected in their announcement speeches. Obama attacked a politics that “has become so bitter and partisan” and pledged himself to “our common interests and concerns as Americans.” Clinton spoke proudly of her ability to take on partisan foes. “I have never been afraid to stand up for what I believe in or to face down the Republican machine,” she said. “I know how Washington Republicans think, how they operate and how to beat them.”

Yet if Clinton and Obama present different profiles, they are, in certain respects, very much alike.

Both have displayed an unusually sophisticated and apparently genuine understanding of the role of religious faith in American politics. Both pride themselves on their ability, proved in their home states, to win over political moderates and voters not tethered to ideology.

And the woman who would become the nation’s first female president and the man who would become its first African American president know how important the men and women of the white middle class will be to the outcome of the next election. Such voters are likely to determine if either of them gets to become a national trailblazer — and also if any other Democrat can find a way to get in the middle of their fight.

E.J. Dionne Jr.’s e-mail address is postchat(at symbol)aol.com.

Copyright 2007, Washington Post Writers Group

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