WASHINGTON -- Tommy Thompson, the former Health and Human Services Secretary under President George W. Bush who is now vying for Wisconsin's open U.S. Senate seat, recently cited the homeland security experience he gained "after 9/18" as proof that he would be able to hit the ground running if elected in November.

While his campaign initially implied that he had misspoken, and had intended to reference the Sept. 11, 2001 attacks instead, an aide now insists that Thompson was referring to the anthrax letters mailed to members of Congress seven days later.

Thompson, a former Wisconsin governor who served in the Bush administration from 2001 to 2005, made his comments during a June 4 speech to the Lake Country Area Defenders of Liberty in Oconomowoc, Wis.

"[A]nd you want a United States senator that is not going to have to go there and find out where the bathrooms are and learn on the job," he said. "I've been there, I ran one of the largest departments in the federal government."

To underscore his experience, Thompson talked about his response to the 2001 al Qaeda attacks on the United States.

"And then after 9/18, I was responsible for the public health of all Americans, responsible for preventing any attack using weaponized medicines like the plague, like smallpox, like anthrax, like tellurium," Thompson said. "And I was responsible for all that. So there's hardly anybody that has the knowledge or the base of knowledge that I do."

The comments were first highlighted by the site Blogging Blue, and the video of Thompson's remarks was provided to The Huffington Post by a Democratic source in Wisconsin.

HuffPost contacted the Thompson campaign before publishing this article to ask if the former governor had intended to reference Sept. 11, 2001, or if Sept. 18 was in fact a significant date.

"There are two plausible explanations as to the recent 9/18 versus 9/11 reference made by Tommy Thompson at a recent event," said campaign spokesman Brian Nemoir. "First, the entire civilized world has the wrong date of this historic and tragic attack on our nation's soil; second, during a spirited campaign appearance Tommy Thompson misspoke regarding an horrific episode in our country’s history during which he played a key leadership role. The campaign is fully examining both scenarios."

He declined to answer a follow-up question on whether that meant Thompson had misspoken.

But after the article was initially published, Nemoir contacted The Huffington Post again and clarified that Thompson was actually referring to the date the anthrax letters were received.

"As a point of clarification, 9/18/01 is in reference to the anthrax attacks on specific members of congress and varied members of the news media," wrote Nemoir. "In-total, it is believed that seven letters were mailed containing anthrax spores, contaminating 22 people of which five people died. As Secretary of the Department of Health and Human Services, lead the efforts to protect our nation from these bio-threats."

Thompson is competing against state Assembly Speaker Jeff Fitzgerald, businessman Eric Hovde and former Rep. Mark Neumann for the GOP Senate nomination in Wisconsin. The winner will face Rep. Tammy Baldwin (D-Wis.) in November.

With high name recognition, Thompson is currently leading in the polls. A recent survey by Marquette Law School gave him an 8 point lead over Baldwin. In the primary, 34 percent of likely voters back Thompson, compared to 16 percent for Neumann, 14 percent for Hovde and 10 percent for Fitzgerald.

Transcript of Thompson's remarks:

And you want a United States senator that is not going to have to go there and find out where the bathrooms are and learn on the job. I've been there, I ran one of the largest departments in the federal government.

I'll give you how big my department was: We have all the children programs, all the elderly programs, all the welfare programs, all the social services programs, all the drug production programs, we run FDA which regulates 25 percent of the gross national product, run CDC which is the organization that determines what an infectious disease is, ran the National Institutes of Health which is the greatest research center in the world, responsible for all the Native Americans and Alaskan Natives' health, responsible for all the international health of anybody that's coming to the United States.

And then after 9/18, I was responsible for the public health of all Americans, responsible for preventing any attack using weaponized medicines like the plague, like smallpox, like anthrax, like tellurium. And I was responsible for all that. So there's hardly anybody that has the knowledge or the base of knowledge that I do. If you want a conservative that can change things around, that is going to make the tough decisions right now, you want me, and I make no bones about it.

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