Former state Sen. Kent Sorenson received thousands of dollars in "under the table payments" before switching loyalties from U.S. Rep. Michele Bachmann, whose state campaign he headed in Iowa, to then-U.S. Rep. Ron Paul, and then lying to federal investigators about the money, according to the U.S. Department of Justice. Prosecutors refused to say which campaign paid him.
Sorenson was seen as a key endorsement early in the 2012 Iowa campaign, as a popular figure in the emerging tea party movement. Iowa's presidential caucuses are closely-watched early tests of campaign strength and candidate popularity.
Sorenson was named Bachmann's state campaign chairman in June 2011, but Bachmann's rise had stalled by that fall. Six days before the Iowa caucuses, Sorenson announced his support for Paul.
In the plea agreement, Sorenson admitted receiving and lying about monthly payments of roughly $8,000 from October to December 2011, when he was still named Bachmann's state chairman.
He pleaded guilty to obstruction of justice and causing a campaign to falsely report expenditures. Sorenson could face up to 20 years in prison for obstruction of justice, and as many as five years on the second charge.
Messages left by The Associated Press with Sorenson and representatives for Bachmann and Paul weren't immediately returned Wednesday.
Sorenson, 42, resigned from the Iowa Senate a year ago, less than three years after his election. However, he has said his decision was "absolutely not" an admission of wrongdoing.
His resignation came just hours after Mark Weinhardt, a special prosecutor asked to investigate whether Sorenson had broken Iowa Senate rules, released a report saying it was "manifestly clear" Sorenson negotiated payments in 2011 in exchange for his work as Bachmann's Iowa campaign chair.
Such payments violate the state Senate's rules that forbid any sitting lawmaker from being paid by a campaign while in office.
The criminal complaint against Sorenson came after questions emerged during the Senate ethics committee investigation about his role in the Bachmann campaign.
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