CHICAGO (CBS) — Democratic challenger Tammy Duckworth is trying to raise questions about who exactly is behind a SuperPAC she says has raised nearly $2 million for her opponent, Congressman Joe Walsh.

8th District Democrat Tammy Duckworth is quick to say she would like to see all of those big-money political action groups eliminated, even the ones that back Democrats like her.

But, Duckworth says she has her suspicions about who’s behind the so-called “Now or Never” Super PAC, which has contributed heavily to incumbent Republican Joe Walsh’s campaign.

She says her campaign has learned one of the groups behind Now or Never’s money was—apparently—co founded by Joe Walsh.

Senator Dick Durbin—a Democrat—says Walsh ought to explain.

Newsradio has reached out to Walsh, seeking a comment.

LISTEN: WBBM Political Editor Craig Dellimore Reports

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