Yes of course – congressional (and legislative) reapportionment won’t happen until after 2010, and after the next general election. But now, with this 2008 election under out belts, we actually have enough raw material to work with to evaluate how congressional-level reapportionment might play out in another two and a half years or so.

For one thing, we have what looks like a stabilizing political picture in most places around the Northwest – after some years of change, the partisan balances for most races changed less this election than in the last, or even the election before that. That’s no guarantee of the future, of course, but some reason to be believe that areas running generally Democratic or Republican now may not change enormously in the near term.

The economic slowdown is a relevant factor too, since population growth is likely to slow, relatively locking into place a number of existing patterns.

So what might we be looking at?

First, mostly the number of congressional seats we have now. Idaho is almost certain to stay at two seats after 2010 (though if growth picks back up, a third in the round after that may be realistic). Washington is closer to a gain of one seat, though the odds look less than even. Oregon is a close call, though, and various studies have estimated it just within or just outside the margin for a one-seat pickup. It’s close enough that we probably can’t know with any certainty until after the census is in.

Given all that, what might the legislatures and governors in the three states do about divvying the districts?

Bear in mind first the differing theories about whether you’re better off with a districts that has lot of variety in it, or a district more homogenous, more of one kind. Of such arguments will politicians be grappling – and spinning.

IDAHO. The last time congressional reapportionment really mattered in Idaho was more than 40 years ago, in 1966, when Ada County was shifted from the second to the first congressional district. Ada was Republican, while the rest of the 1st district then was fairly closely balanced between the parties; that shift gave the first a Republican lean that persists today.

Except for a couple of odd situations. One is that the 1st this year actually elected a Democrat, Walt Minnick. And the other is that the 2nd district, because the city of Boise now leans Democratic, is less Republican than the 1st. Assuming Minnick is re-elected in 2010 (not that we automatically assume it – it will be a battle – but he will be the incumbent), the split between the districts could be a big battle again. The exact run of the border line through Ada County could be bitterly fought over. And you could see the idea of a few rural Republican counties (Lemhi, Custer) brought into the 1st to redden it up. Or maybe 2nd district Representative Mike Simpson, who has a safe seat, is considering moving on, and Republicans in control of the legislature don’t want to shift Republican votes out of the 2nd. The line between districts could be the first of interest in Idaho in a long time.

WASHINGTON. Washington very likely keeps its nine seats, and they are likely to be juggled around a little. Not enormously. The two geographically large districts east of the Cascades, both currently strongly Republican, are unlikely to change enormously. And of the seven districts to the west, six are held – and in recent elections, strongly held – by Democrats, so even a little shifting between them isn’t likely to generate major outcome changes.

However, there is the case of District 8, a geographically small district in eastern King County with significant population bases – mostly Democratic – to its north, west and south. Democratic remappers would like to turn this district blue, and they could probably do that with ease. Imagine, for example, throwing a slice of Seattle into this district: That could be fatal for any Republican candidate in a district currently pretty closely balanced, and it could be done without much reddening in, say, the Seattle-centric 7th district. There’s not a particular reason to think Washington’s House delegation will shift in 2010 from its current 6-3 Democratic, but in 2012 it could easily go 7-2 based on remapping.

OREGON. Here’s the biggest area of interest, and not just because of the close to even odds the state may get another House district next time.

There’s a great post and line of discussion on Blue Oregon about how the state might be split into either five or six districts next time. One poster, drawing on the growing blue voting patterns statewide, argues that giving Republicans one safe district (the 2nd, which includes everything east of the Cascades and part of southwestern Oregon) isn’t necessary – Five districts could be devised giving Democrats an edge in all. He writes: “All five districts now have a Democratic lean, but none are absolutely safe should a Republican wave year happen. I say it’s worth it to have the default be five Democratic districts, instead of four mostly safe seats and one where we can barely compete at all.”

It’s an intriguing map, creating a coastal district (which runs in the north from just northwest of Portland, south along the coast, and inland to Medford); another running from east Portland due east, mostly along I-84, all the way to Hells Canyon; another including most of east-of-Cascades but balanced on the west by Lane and Douglas; a central Portland metro district; and a fifth including still another slice of Portland, south through Clackamas to the Salem area and over the mountains to include the area around Bend. Cleverly drawn; Democrats could realistically win in all, though the drafter acknowledges that most of them could be lost by Democrats too, come the next strong Republican year.

The picture gets even more interesting if you throw in a sixth district: “Ashland, Bend and the Gorge are either keystones of a new blue inland district, or they’re wasted on a district that will never be won. Let’s discuss which it is.”

Odds are that in Oregon as in Washington Democrats will be drawing these lines. Doesn’t mean the decisions will come easy, even so.