The scandal that refuses to go away, the blunder that cripples a candidacy, the error that defies every effort at correction — this is what the Rev. Jeremiah Wright has become for Sen. Barack Obama’s campaign.

In early March, when an ABC News report pushed Wright’s incendiary sermons into the national news spotlight, it was possible to believe that the uproar would be a short-lived controversy.

Americans would be shocked by video footage of Obama’s pastor shouting “God damn America” from his Chicago pulpit, but political observers reasonably expected the damage would be limited and of short duration. The candidate would face questions from the media, he would downplay or disavow the inflammatory remarks, the campaign would move forward, and the controversy would fade from memory — such is the standard political playbook for dealing with these kinds of imbroglios.

That hasn’t happened with Wright, however, and the failure of the Obama campaign to deal properly with this scandal may ultimately doom Obama’s candidacy.

MONDAY AFTERNOON, following Wright’s appearance at the National Press Club, former Clinton adviser Dick Morris appeared on Fox News and compared Obama’s plight to that of Michael Dukakis in 1988 — but added that, unlike Wright, “at least Willie Horton shut up [because] he was in prison.”

The case of Willie Horton — the convicted killer who went on a crime spree after being furloughed under a program defended by Dukakis — comes easily to mind in any case of a racially explosive issue involving a Democratic candidate. Yet the analogy is ill-suited for the problem that Wright poses to the Obama campaign.

The Horton case became a legitimate issue in the 1988 campaign because it touched directly on Dukakis’s policies as governor and thus reflected the candidate’s overall stance on criminal justice issues. No one can yet point to any official action by Obama that reflects the “black liberation theology” espoused by Wright.

Because of the fundamental irrelevance of Wright’s sermons to Obama’s record in public office, it would have been the easiest thing in the world for the candidate to condemn the pastor’s most outrageous statements and then return to campaigning. Yet that didn’t happen, and Obama has only himself to blame.

A few days after the ABC News broadcast about Wright, Obama decided to travel to Philadelphia and give a nationally-televised speech about race, nearly 5,000 words long, during which he attempted to explain away Wright’s rants, saying, “I can no more disown him than I can disown the black community.”

While the Philadelphia speech immediately drew rave reviews from the media, in hindsight it looks like the first unforced error of Obama’s campaign. If, as Obama suggested, Wright was morally coterminous with “the black community” — so that the candidate could not “disown” one without disowning the other — then wouldn’t the reverend and his opinions be newsworthy subjects deserving further scrutiny?

Wright seems to think so, and thus the pastor’s recent media tour, including an appearance with Bill Moyers on PBS, a Sunday speech to an NAACP meeting in Detroit and the Monday morning event in Washington. Defending Louis Farrakhan in his National Press Club appearance — with notorious anti-Semite Malik Shabazz in attendance at an event where Nation of Islam members reportedly provided security — it was as if Wright was daring Obama to “disown” him now.

OBAMA’S PREDICAMENT now resembles nothing so much as that faced by George McGovern in July 1972, after the Democratic presidential nominee belatedly discovered that his vice-presidential choice, Missouri Sen. Thomas Eagleton, had previously been hospitalized for mental illness.

As with Obama’s mishandling of the Wright controversy, the Eagleton disaster was an unforced error on McGovern’s part. McGovern and his campaign team had dawdled over choosing a running mate, evidently in the mistaken belief that Ted Kennedy could be talked into taking the No. 2 spot.

When Kennedy finally gave a definitive “no,” and other top possibilities also declined, the McGovern campaign scrambled and came up with Eagleton. There was no time for a background check and when Eagleton was asked if he had any skeletons in his closet, he said he didn’t — even though he’d been hospitalized three times for severe depression and had twice undergone electroshock therapy.

It was only after he’d been nominated as vice president that journalists began reporting about Eagleton’s history of mental illness. Rather than to take responsibilty for his deception and resign from the ticket, however, Eagleton tried to hang on. The Democratic campaign endured more than a week of agonizing limbo — at one point, McGovern famously declared he was behind Eagleton “1,000 percent” — before Eagleton was finally forced out.

Some say Richard Nixon would have been re-elected in 1972 no matter what, but McGovern’s mishandling of the Eagleton affair destroyed whatever hope the Democrats had.

OBAMA’S MISHANDLING of the Wright controversy resembles the Eagleton affair in that it reveals a lack of foresight and preparation. Wright’s sermons were available for sale on DVD, and Ronald Kessler of NewsMax.com had reported about Wright’s controversial views as early as January. Yet when the ABC News story broke in March, the Obama campaign appeared to be caught flat-footed.

Much like McGovern’s initial “1,000 percent” support of Eagleton — which only encouraged Eagleton’s attempts to stay on the ticket — Obama’s Philadelphia speech defending Wright has prolonged the crisis, with Wright now refusing to leave the spotlight.

And, like McGovern in ’72, Obama finds himself with no good options. If he fails to repudiate Wright’s racialized theology, Obama can’t hope to win in November — and Sen. Hillary Clinton’s campaign has made “electability” a crucial part of her appeal to the superdelegates who will ultimately choose the Democratic nominee. But if Obama does repudiate Wright, it will contradict his earlier statement that doing so would be to “disavow the black community.”

Obama could have put this controversy behind him six weeks ago. Instead, the candidate of Hope and Change allowed it to mushroom into a crisis that threatens to undermine whatever hope for change the Democrats might have in 2008.