When they take it up for a vote Wednesday, expect aldermen to kvetch about the 2009 budget even as they pass it–and by a large margin.

Nothing new there. In fact, it’s another reason why the City Council is so ill-equipped to fight for major budget revisions: there’s no structure or precedent for it. Aldermen simply don’t carry much weight on the budget, even though oversight of it is arguably their most important oversight legislative job.

A year ago, when the economy was showing signs of a slowdown, the council signed off on the mayor’s 2008 budget, with its millions in tax and spending increases, by a 37-13 vote. (A separate ordinance specifying the tax hikes generated more resistance but still passed 29-21.) That amounted to the most opposition to a Daley budget in 16 years, since the still-new mayor had to fight for 30-18 passage of his 1992 plan. Starting in 1993 (when the 1994 budget was passed), the council went 14 straight years without more than four votes against an administration budget; in seven of those years, the votes were unanimous. Were all of the budgets sound, fair, and just what the city needed? Aldermen said so.

A few aldermen do take pride in shouting out nay at budget time. The alderman with the most no votes under Richard M. Daley is the 46th Ward’s Helen Shiller, but she hasn’t uttered anything but aye for almost a decade now. In the past few years it’s been Toni Preckwinkle of the Fourth Ward who’s been the mayor’s leading annoyance.

In case you’re as geeky about such things as some of the rest of us, here ya go: This chart shows how the votes have gone down every year since this Daley has been mayor. (Again, the budget is always voted on at the end of the previous year. The 1990 budget, in other words, was approved at the end of 1989. DNV=Did Not Vote, for whatever reason.)