Illinois Attorney General Lisa Madigan has surged to the lead among Democrats on the list of favorites to take Barack Obama’s place in the U.S. Senate at the expense of Rep. Jesse Jackson Jr., whose image clearly has suffered in the growing Blagojevich scandal.

Thirty-two percent (32%) of Illinois Democrats now say Madigan should be named to the seat vacated by Obama, the state’s junior Democratic senator, according to a Rasmussen Reports telephone survey of Illinois voters taken Wednesday night.

In a Rasmussen Reports survey last week, Jackson was the top choice of a plurality of the state’s Democratic voters (36%), but with the revelation that he is “Senate Candidate 5,” his support has been cut in half to just 18% now.

A week ago, Madigan was third on the list of five favorites among Democratic voters, with 17% support.

Sixty-six percent (66%) of all Illinois voters say the state should hold a special election to fill Obama’s Senate seat rather than let Governor Rod Blagojevich or his successor appoint a replacement. Twenty-one percent (21%) disagree, and 13% are undecided.

Among Illinois voters, 74% of Republicans, 66% of Democrats and 60% of unaffiliated voters favor a special election. Obama still has two years remaining in his Senate term.

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Blagojevich and his chief of staff were arrested Tuesday by FBI agents after being charged with federal corruption counts including trying to sell Obama’s seat to the highest bidder. Court documents quote Blagojevich in wiretapped phone conversations saying a representative of Senate Candidate 5 would raise money for him in exchange for the Senate appointment. Jackson, who has openly campaigned for the job, emphatically denied offering Blagojevich anything in exchange.

Eighty-four percent (84%) of Illinois voters say that Blagojevich should resign and 79% say he should go to jail.

Madigan is threatening to ask the Illinois Supreme Court to declare Blagojevich unfit to hold office if he doesn't resign.

Pat Quinn, the state’s lieutenant governor, says if he becomes governor, he may appoint Obama’s successor rather than wait for a special election.

Madigan was the number one choice of Illinois voters overall in last week’s survey, favored by 25%. She is now the favorite of 32% of the state’s voters, followed by Tammy Duckworth, director of Illinois’ Department of Veterans Affairs, with 18% support, down three points from a week ago. Duckworth is the first choice of 20% of Illinois Democrats, compared to 29% last week.

Eleven percent (11%) now favor Jackson versus 23% a week ago.

Rep. Jan Schakowsky, a Chicago-area member of Congress like Jackson, is the choice of 10% of the state’s voters and seven percent (7%) of Democrats. Emil Jones, president of the state Senate and a top Blagojevich loyalist until this week, is the first choice of one percent (1%) of Democrats and three percent (3%) of Illinois voters overall. These numbers are largely unchanged from a week ago.

Twenty-seven percent (27%) of Illinois voters are undecided who should be their next senator, compared to 21% last week.

Prior to the indictments, Madigan, a rising political star in Illinois, already had been expected to challenge the highly unpopular Blagojevich for the Democratic gubernatorial nomination.

Jackson’s plunging numbers pose a delicate problem for Democrats since the African-American community, perhaps the party’s most loyal base, has been insisting that a candidate such as Jackson or Jones succeed Obama, who was the only black U.S. senator.

Duckworth, who lost both her legs while serving in Iraq and was an unsuccessful candidate for the House this year, has the support of Obama’s chief of staff Rahm Emmanuel and Senate Majority Whip Dick Durbin, Illinois’ senior senator.

Obama has not endorsed anyone for the seat which he resigned following his election as president.

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