Was Limbaugh's "Operation Chaos" successful in Indiana?

Even as Barack Obama's campaign celebrated Tuesday's primary results, aides charged Wednesday that they would have had an even stronger showing were it not for meddling by an unlikely booster of Hillary Rodham Clinton: the popular conservative radio host and longtime Clinton family nemesis Rush Limbaugh.

The impact of Limbaugh's "Operation Chaos" emerged as an intriguing point of debate, particularly in Indiana, where registered voters could participate in either party's primary, and where Clinton won by a mere 14,000 votes. As he had before several recent primaries, Limbaugh encouraged listeners to vote for Clinton to "bloody up Obama politically" and prolong the Democratic fight.

Limbaugh crowed about the success of his ploy all day Tuesday, featuring on-air testimonials from voters in Indiana and North Carolina who recounted their illicit pleasure in casting a vote for Clinton. "Some of the people show up and they ask for a Democrat ballot, and the poll worker says, 'Why, what are you going to do?' He says, 'Operation Chaos,' and they just laugh," Limbaugh said Tuesday.

But Limbaugh called off the operation Wednesday, saying he wants Obama to be the party's pick because "he would be the weakest of the Democrat nominees."

He added: "He can get effete snobs, he can get wealthy academics, he can get the young, and he can get the black vote, but Democrats do not win with that."

The Obama campaign and many of its supporters condemned Limbaugh's intervention tactic Wednesday, calling it a major factor in Clinton's narrow Hoosier-state win.

"Rush Limbaugh was tampering with the primary, and the GOP has clearly declared that it wants Hillary Clinton as the candidate," Sen. John Kerry, D-Mass., an Obama supporter, told reporters on a conference call. On the same call, Obama campaign manager David Plouffe said Limbaugh was "a clear factor in the outcome."

Whether that is true remains in question. Even if Limbaugh's exhortations brought as many of his listeners to the polls as he says, his operation did not cripple Obama, who emerged stronger from the day's primaries after better-than-expected showings with some key groups of voters.

Those looking for evidence of Limbaugh's influence pointed to Clinton's edge among Republicans in Indiana and North Carolina. In Indiana, 10 percent of Democratic primary voters described themselves as Republicans, a higher rate than in any state but Mississippi, and they went for Clinton by 8 percentage points, according to exit polls. In North Carolina, they were 5 percent of the electorate, and went for her by 29 points.

By contrast, Obama won Republican voters, often by very large margins, in seven of the eight states where exit polls were able to report the group before the Texas and Ohio primaries on March 4, when Limbaugh first coaxed listeners to vote for Clinton.