John Kerry returned to Washington last week and did something surprising for a defeated Democratic presidential nominee. He met with his party’s leaders in the House and Senate to plot strategy for the upcoming year.

Those who supposed Kerry would disappear on vacation, put on a few pounds, grow a beard, make an American Express commercial, or teach at a small college raised their eyebrows: Kerry might actually be serious about playing an important role over the next few years. He might even be planning another presidential run.

This scenario would not be surprising if Kerry were a Republican. GOP contenders are groomed over a long period, and losing is often a part of the credentialing process.

Presidents Richard Nixon, Ronald Reagan, and George H. W. Bush ran unsuccessful campaigns before winning — with Reagan twice falling short of the GOP nomination and Nixon failing once as the nominee, followed by a more embarrassing defeat for governor of California.

As a result, Republicans almost always nominate a familiar, tested brand — a Nixon, Reagan, Bob Dole, or Bush — who knows every whistle-stop and pothole on the national campaign trail the way an expert skier knows the bumps on a favorite mountain. (George W. Bush got the lay of the land from his father’s two decades in the national spotlight.)

The Democrats, meanwhile, begin every cycle afresh, as though looking for a caped crusader to lead them to the White House. Presidents Jimmy Carter and Bill Clinton could not have been picked out of a police lineup outside their home states before launching their national campaigns. And past nominees George McGovern, Michael Dukakis, and Kerry were all unknowns on the national stage, stepping out of the chorus to sing the lead.

Since Democrats’ first allegiance is usually to their causes, not their leaders, losing candidates get discarded quickly. As Ted Kennedy once said in a concession speech scripted by eight-time losing consultant Bob Shrum, ”The cause endures.” But a candidate’s shelf life expires immediately.

One reason Democratic candidates so often fall prey to Republican efforts to ”define them” through negative ads is that they are undefined to begin with. Lately, this seems to have become a staple of the Republican game plan, as Clinton noted at the Democratic convention.

”Since most Americans aren’t that far right, our friends have to portray us Democrats as simply unacceptable, lacking in strength and values,” Clinton advised the party faithful.

…Voters knew Bush; they did not know Kerry. So despite the Democrat’s best effort to appear strong, a broad-brush characterization of Kerry as weak was enough to send some voters scurrying back to Bush. If voters had seen more of Kerry over the past few years and had their own observations to guide them, they would not have been so easily swayed.

…Over time Kerry might decide that after running the costliest Democratic campaign ever, only to win the exit polls but lose the presidency, he cannot bear to return to square one.

But there is every reason to believe that he — as well as Edwards and Dean — would be better candidates for having run before. And the country would get less talk of swift boats, screams, or hair products, and more of a chance for serious debate.

Boston.com: In ’08, familiar faces could aid Democrats: 11/16/2004

More here: WashPost: After the Race, John Kerry Climbs Back Up the Hill. This is a guy you can’t help but respect – that is – if you don’t let Karl Rove define him for you.