UPDATE 4/27: Looks like Renzi is putting up a fight. This should be entertaining and embarrassing for the GOP. Every day Renzi hangs on is another day of negative press that helps CD 1's voters decide that a Democrat might better represent their interests.
Tedski at Rum, Romanism and Rebellion is predicting Renzi's resignation by tomorrow. I don't know if it will happen quite that soon, but I wouldn't be surprised. The signs are all flashing red. The GOP leadership has completely shut Renzi down, allowing him to save face by resigning from his committee positions and caucus funding programs instead of stripping him outright. Renzi is essentially under House arrest (little pun).
I believe the whispers of Renzi's impending resignation are largely accurate not only because my schaudenfruede runneth over, but because Renzi has made himself a major liability to the GOP's capo di tuti capo: President Bush. Renzi is focusing yet more light on the Administration's biggest headache, Attorneygate. The GOP leadership has got to want him out of Congress to minimize his press profile and get ahead of the inevitable calls for his resignation. The GOP leadership's tolerance for ethical and legal troubles has taken a steep dive since losing their majority, largely on that issue.
If the FBI hadn't raided the Renzis' Patriot Insurance Co., there wouldn't be nearly this pressure: compare Renzi's dilemma to Wilson and Dominici in NM, who are guilty of much more naked pressure on their USA than is Renzi. Unfortunately for Renzi, the appearance of an attempt to improperly influence a USA combined with a genuine underlying crime that the FBI is serving warrants on and Federal Grand Jury is sitting on equals a get out of Congress free card.
So, our Governor will need to set a special election to replace Renzi, since we are more than 6 months out from a general election and Renzi is not going to survive until next month, let alone the middle of next year. Within 105 days of the resignation, when it comes, there will be primary elections. Given the extremely short time horizon, only those with existing name recognition, political reputation, and lots of friends with money need apply. My money is on Kirkpatrick or Simon for the Democrats.
I think the Republicans are irrelevant unless the national and state parties throw major bank on a candidate, which is certainly possible. Even then, the likelihood of the GOP retaining the seat, as Renzi's shame unravels in the midst of the special election, seems slim unless the GOP candidate can steer clear of any bruising in the primary and has a compelling story as to why he's not more of the same.
Within 45 days of the primaries, a general election must be held. If the predictions of a early resignation by Renzi are correct, we could be in general election in CD 1 by September. At that point, Arizona's Congressional delegation will most likely turn blue as we pick up CD 1, which we should have won 2008, for a 5D/3R delegation.