Like a big flood that tears through the countryside, Wednesday's developments have changed the course of Illinois politics, perhaps more than any single day since pol-busting U.S. Attorney Jim Thompson announced for governor and ushered in 25 years of GOP rule.

  The only question is, how much. We won't know for sure until all the water recedes.

   Wednesday's combination of Lisa Madigan's decision to re-up for attorney general, and John Harris' decision to testify against Rod Blagojevich and others, appears at this writing to have made some careers while ending others. Here's the tentative list of winners and losers.

   * Winner: The Illinois Republican Party. Ms. Madigan was the  solid-to-overwhelming favorite whether she ran for governor or senator, regardless of who the GOP put up. Now that she's gone, it looks like one of the few A-list Republicans around, North Shore Congressman Mark Kirk, will run for the Senate. He'll be an underdog, but has a shot.

    Ditto for governor, where whoever the Dems put up will be weaker than Ms. Madigan. That gives the GOP a chance. None of those now running has yet lived up to their potential, particularly state Sen. Kirk Dillard of Hinsdale. But it's early.

   The one sure GOP loser: AG contender Joe Birkett, who announced for general a few days ago when most insiders figured Ms. Madigan would vacate the post.

  The DuPage County state's attorney ought to save his money and try for something else, maybe a judgeship. Odds are better that I'll get carded at the bar tonight than Joe will beat Lisa.

  * Winner: Gov. Pat Quinn or Comptroller Dan Hynes, depending on who emerges from a likely Democratic primary battle between them next February.

   Both benefit from the absence of Ms. Madigan from the race. But the same challenge faces each of these two wonkish, unglitzy officials: Dramatically stepping up their game. If Mr. Quinn loses, this is his last hurrah. If Mr. Hynes stays on as chief state beancounter much longer, his career is over.

   * Loser: Illinois GOP Chairman Andy McKenna. His trip to Washington, D.C., this week to explore a bid for the U.S. Senate couldn't have been more ill-timed. I'll take it back if Mr. Kirk changes his mind and doesn't run. But I doubt that.

   * Loser. Ex-Gov. Rod Blagojevich. Any real doubt that G-Rod is going down likely was removed when Mr. Harris, his former chief of staff, agreed to plead guilty and talk details about what Rod wanted for Barack Obama's Senate seat.

    My favorite clause of Mr. Harris' plea deal is how Rod squawked when he was told that a foundation job he might get in exchange for appointing the right person to the Senate would pay $200,000 to $300,000. "Is that all?"  he allegedly replied. But G-Rod had "a more positive reaction" when Mr. Harris told him the pay might hit $500K a year, according to the plea agreement. Nice.

   The real question: Who else might Mr. Harris incriminate?

   * Winner and loser: Michael Madigan, the speaker of the Illinois House, chairman of the Illinois Democratic Party and anointed emperor unofficial of all that moves under the Capitol dome.

   Mr. Madigan sent clear word that he didn't want to step down from any of his posts, and now he won't have to. I understand his reluctance to go, particularly in the last election before legislative remap.

  But the speaker now is hurting the career of daughter Lisa. He's become a huge weight around her neck, one that would have badly slowed her in 2010 in a race for governor and one that will persist in 2014.

   * Winner: We the people, because the race for the Senate seat looks like it will include a nice range of interesting contenders, including Mr. Kirk the Republican and Democrats Alexi Giannoulias, Cheryle Jackson and Chris Kennedy.

    More later. It's going to be a busy few weeks.