(Updated with response from the Bachmann camp.)

Garrison Keillor, humorist and host of radio show “A Prairie Home Companion," invoked his fictional Minnesota town of Lake Wobegon to make a fundraising pitch Thursday for sixth district challenger Tarryl Clark.

Keillor wrote that Lake Wobegon was “smack in the middle of Minnesota — in Minnesota's sixth congressional district,” and said it was “embarrassing to me and a great many Minnesotans” that Rep. Michele Bachmann represented the district.

In the e-mail to Clark's supporters titled, "Defending Lake Wobegon," the humorist accused Bachmann of “grandstanding and giving interviews to Fox News” instead of working for the district, echoing an attack line the Clark campaign has used.

Bachmann campaign spokesman Sergio Gor responded that Keillor's pitch "is yet another sign of a desperate campaign."

"The quota on comedy in Minnesota has been reached with the election of Al Franken," Gor said. "Garrison Keillor should stick to what he knows best, which is fabricating make believe stories."

Today is the final day for third quarter fundraising, and many candidates are sending out last-minute fundraising e-mails.

Keillor, who lives in St. Paul, is frequent donor to Minnesota Democrats. He’s given Clark $4,800 this campaign cycle, according to Federal Election Commission filings.