The short answer: It depends. It depends upon what Abramoff is telling prosecutors and what he is willing to testify to in court. And until we know the answers, we cannot really begin to gauge the plea's political ramifications.
Two other big questions are also unanswered. First, is Abramoff able and willing to implicate former House Majority Leader Tom DeLay, R-Texas, in any serious wrongdoing? Second, will Abramoff implicate just five or fewer members of Congress -- largely those already linked to him in numerous news accounts -- or, will a half-dozen or more lawmakers find themselves dangerously exposed?
Democrats loathe DeLay and would love to see him brought further down, regardless of whether his difficulties affect the makeup of the next Congress. But if DeLay is directly implicated in Abramoff's criminal activities, the scandal could acquire a Republican tinge in the minds of the public.
So far, the vast majority of voters have no earthly idea who Abramoff is, and they don't see his troubles as primarily a Republican problem. The chances of this becoming a GOP scandal rather than a bipartisan congressional scandal would go up enormously if DeLay were indicted or were to plead guilty to a serious crime. Otherwise, Democrats will have much more difficulty scoring political points off Abramoff's plea.
It's difficult to estimate how many incumbents the firestorm will embroil. Some good-government groups estimate that more than 100 members of Congress are implicated. These "goo-goos" count every lawmaker who ever accepted a contribution from any organization even remotely tied to Abramoff. Other estimates of 25 to 50 members seem to be plucked out of the air. Then there is a more reasonable estimate -- between six and 12.
Whatever the eventual total, another key question is, do the tainted lawmakers largely belong to one party? And will the next round of charges spur a flurry of congressional retirements? If it does, what party do those departing members belong to, and how many of them represent potentially competitive districts?
If the number of open House seats remains small -- today, there are only 14 Republican open seats and seven Democratic ones -- the November elections probably won't produce huge changes. With House re-election rates averaging about 95 percent (even in incumbents' worst years, about 80 percent get re-elected), the number of open seats, particularly the number in swing districts, is a strong determinant of how many seats end up changing parties.
If the scandal pushes a half-dozen or so Republicans in competitive districts to retire and doesn't push a similar number of Democrats, then Democrats' chances of making a net gain of 15 seats -- and, thus, taking control of the House -- would rise from perhaps 15 percent to 25 or 30 percent, or more. That would make Election 2006 much more interesting than it looks today.
Republicans are probably more caught up in the Abramoff scandal than Democrats are for a few simple reasons: First, Abramoff is a lifelong Republican, and lobbyists usually work their own side of the street more than the other side. Second, Republicans control both ends of Pennsylvania Avenue, so influence-peddlers tend to gravitate to them.
The bottom line: Despite Abramoff's plea, we don't really know much more today than we knew a week ago. For months, it has been fairly clear that Abramoff was going to be tried or was going to cut a deal, and that, sooner or later, members of Congress who played in Abramoff's sandbox would be called to account.
Very soon, the congressional names and numbers involved should begin to come out. Then, we can seriously begin to calculate the potential fallout for the midterm elections.