A statistical rundown of presidential votes by congressional district has been completed - for the three Northwest states at least - on the Daily Kos site, and it offers some real perspective on just how Republican or Democratic the various districts in the states are.
This is least useful, probably, in Idaho, where the two congressional districts are very nearly each as Republican - very. It does show that the second district is incrementally less Republican than the first; In 2012 it went 33.1% for Barack Obama and 64.1% for Mitt Romney (in 2008, 37.1% for Obama and 60.5%) for John McCain). That compares with the first district's 2012 of 32.2%/Obama and 64.9%/Romney (in 2008, Obama/35.1% and McCain/62.5%) - hardly a difference at all, when the overall margins are so large.
In Oregon's five districts, which like Idaho's didn't change massively with redistricting, the numbers are a little more distinctive.
By far the most partisan-leaning district of the five was the Portland-centric 3rd, where in 2012 Obama took 72% (Romney/24.7%) and in 2008 won with 72.9% (McCain/24.3%) - a much more sweeping partisan dominance than even Republicans in Idaho. It was also much more sweeping than in the Republican-oriented Oregon 2nd district, where the Republican presidential nominees won but by less than landslide numbers (2012 Romney/56.8%, Obama/40.5%; 2008 McCain/53.8%, Obama 43.3%). In fact, the appropriate Oregon mirror image to the Republican 2nd now would be not the 3rd, which is much more blue than the 2nd is red, but rather the first district, where Obama both cycles won by about as much as his Republican opponents did in the 2nd (in the 1st: 2012 Obama/57.3% Romney/40%; 2008 Obama 59.6% McCain 37.7%).
The other two districts, roughly the southwestern quadrant of the state, are closely comparable, with clear but lesser Democratic leads. In the 4th (centered on Lane County but including much conservative territory), Obama won in 2012 by 51.7% to 45.0%; in 2008, by 54.2% to 42.7%. In the 5th, the numbers were not far off from that: Obama in 2012 by 50.5% to 47.1%, and in 2008 by 53% 44.2%.
The largest interest in these numbers, though, should be in Washington state.
Here we find a genuinely wide range of results. The single most partisan congressional district in the Northwest is here, in Seattle's 7th district, where the Obama wins both cycles were enormous (79.2% to 18.1% in 2012, and 80.4% to 18.0% in 2008), significantly exceeding even the Oregon 3rd. The third most partisan CD in the region is immediately south of Seattle, the much-reconfigured 9th district, where Obama overwhelmed Republicans in both cycles (in 2012, by 68.3% to 29.6%, and in 2008 by 68.6% to 29.9%).
Of the 10 Washington districts, the Republicans won the presidentials both time in just two, the easternmost. Their strongest was the Tri-Cities-based 4th, where they nearly won landslides both times (2012 Obama 37.9% to Romney 59.7%, in 2008 Obama 39.2% to McCain 58.9%). They approached that in the 5th (2012 Obama 43.7% to Romney 53.5%; 2008 Obama 46.3% to McCain 51.2%). They are clearly Republican-leaning areas, but not overwhelmingly so by comparison with the districts around Seattle.
The 3rd district, now held by a Republican and commonly described as a Republican district, is more marginal than you might think. Romney did win it in 2012, but only narrowly (Obama/47.9%, Rommey 49.6%), and McCain lost it in 2008 (Obama/50.9%, McCain 47.1%). And while the new 8th district has been commonly described as a Republican gift to Republican Representative Davie Reichert, this may come as a shock: Obama won it in both cycles (20120 Obama/49.7%, Romney 48.1%; 2008 Obama 51.5%, McCain 46.8%). Democrats might want not to give up in the 8th.
When it was formed by redistricters, the new 1st district looked maybe a tad more Republican than Democratic, but in any event very close. But the presidential numbers show that new Democratic Representative Suzanne DelBene's win there may be no fluke. Obama won in its contours 54.1%/43.3% in 2010, and by 56.3%/41.9% in 2008.
And the newly-redrawn Washington 6th and 10th look a little more Democratic, based on presidential numbers, than that - about in lines with expectations.
All of which may provide some guidance as political people plan out their races for the cycles ahead.