WASHINGTON — Who picked this movie? A few months ago, the contest for the Democratic presidential nomination looked as if it would be the feel-good political campaign of the decade, if not the century. We settled in for a heartwarming sequel to “Mr. Smith Goes to Washington.” Instead, we’re having to endure an endless loop of “Alien vs. Predator,” a grisly piece of cinema in which all-powerful extraterrestrials battle for ultimate supremacy while mere humans become collateral damage.

Somebody make it stop.

Actually, the better film analogy may be “The Terminator.” (Anything but “Rocky” — or, in the popular Internet video, “Baracky.”) Yes, I know it’s inappropriate to compare a talented and accomplished woman such as Hillary Clinton with a homicidal cyborg from the future. But it’s hard to come up with a better image for the woman’s sheer relentlessness. If she ever says “I’ll be back” while I’m in earshot, I’m getting out of Dodge.

No, I’m not calling for Clinton to get out of the race. It’s ridiculous to advise a candidate who just won Pennsylvania by 9 points to pack it in, even if it’s still hard to imagine a plausible way for her to win the nomination.

And it is, you know; the delegate arithmetic has hardly budged. Clinton would have a realistic chance of eliminating the future rebel leader who someday will threaten the dominion of sentient machines over all of humankind — I mean, defeating Barack Obama — only if her opponent were gracious enough to dissolve into a quivering puddle. She has done everything she can to encourage such a meltdown, but by now it should be clear that it won’t happen.

If anything, Obama is learning some of Clinton’s war craft. He watched as she moved the goal posts so often that they’re not even in the stadium anymore, they’re somewhere out in the parking lot — his lead in delegates didn’t matter, his wins in caucus states didn’t matter, his wins in states below a certain population threshold didn’t matter, his wins in states above that threshold didn’t matter if the states in question were Illinois, Georgia or Virginia. In Pennsylvania, the Obama campaign did a similar thing with Clinton’s victory margin, arguing that if Clinton won by five points or less she would actually suffer a humbling defeat.

But she beat the point spread handily. Our long national nightmare continues.

I still believe that either Democrat will be able to beat John McCain. Millions of new voters and tons of new money are flooding into the Democratic Party, and at least some of this new wealth has to stick. Those surveys of registered Democrats showing that huge numbers of Clinton supporters would never vote for Obama, and that huge numbers of Obama voters would never vote for Clinton, are almost certain to change when disaffected true believers see how little McCain’s political philosophy has to do with core Democratic Party values.

But the longer this slugfest continues, the more the eventual nominee is tarnished in the eyes of independents who are looking for bipartisan solutions to the nation’s problems. Obama, who holds a solid lead of at least 150 pledged convention delegates, clearly would like to shift his campaign into general election mode. But now he has to scrap for every vote in Indiana and North Carolina, which means he has to continue to appeal to the Democratic Party’s activist base — while McCain does photo ops in African-American communities and talks about climate change.

All the extraneous “issues” aren’t helping, either. In a sense, it’s better for Obama to deal with spurious questions about aloofness or patriotism now, rather than in the fall — just as it’s better for Clinton, should she be the nominee, to face questions now about truthfulness or the role she envisions for her husband, Bill. But after a certain point, a candidate isn’t being tempered by adversity. He or she is just getting bashed.

At least until the votes are counted in Indiana and North Carolina on May 6, there’s not much anyone can do to stop the punishment — except the candidates themselves. Democratic Party elders and superdelegates might not be able to end this thing yet, but they can put the campaigns on notice: Fighting hard for the nomination is understandable, but fighting in such a way as to give the presidency to McCain is unforgivable.

Eugene Robinson’s e-mail address is eugenerobinson(at)washpost.com.

© 2008, Washington Post Writers Group

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