When you go into Obama-campaign style "Fight the Smears" mode, it's generally a pretty good idea to be sure the charges against you are, in fact, not provably true.

As Josh Gerstein wrote last week, the story of Sami Al-Arian, the Florida professor who pled guilty of supporting Palestinian Islamic Jihad in 2006, has been roiling the GOP Senate Primary there, with Tom Campbell under fire from rivals for his departures from the party's staunch support for Israel.

Campbell, in last week's debate, defended himself against charges involving a letter he wrote in support of Al-Arian and contributions from the professor:

The reason that I asked for this debate was to exactly have this opportunity. First, I did not give back the money, the campaign was over. There was no funds to give back, unlike President George W. Bush who won his election. Ah well know facts because it was on Bill O'Reilly, that was after the campaign was over and after my letter to University of South Florida.

He also put up a website, CampbellFacts, on the same theme.

The problem: Just hours after the debate ended, The Investigative Project put online a letter from Campbell that defended Arian and made reference to that same O'Reilly interview.

"I read a transcript of the O'Reilly Factor interview last autumn, and I did not see anything whereby Professor Al-Arian attempted to claim he was representing the views of the University of South Florida," Campbell wrote in the January, 2002 letter.

The interview included a clip of Al-Arian saying, "Victory to Islam. Death to Israel," which has produced, today, the race's best defense yet, as Campbell says he didn't actually read that part.

"That's too zealous," he said. "Unacceptable. Calling for death to a country or individual is unacceptable."