With polls showing Democrats Kathy Hochul surging and likely to win today, the spin about what the race means is going to supercede the election itself. Republicans say the race tells you nothing about the Republican budget, which became its central issue, or the state of public opinion. (Here’s some spin from Eric Cantor and American Crossroads.) Mainstream analysts are taking a very cautious approach to interpreting the race. (Here’s a cautious Nate Silver, and an even more cautious Charlie Cook.)

I’m not so cautious. I think the race is quite significant. Yes, the race is almost certainly an outlier, in the sense that if Democrats everywhere could overperform the partisan division of their district as much as Kathy Hochul seems likely to, then they’ll easily sweep control of the House next year. That seems unlikely. Even as an outlier, though, this race fits together with other data to tell us that the political landscape has fundamentally shifted in the six months since the last elections. Take a look at this chart, compiled by Silver, plotting the 2010 House vote against that district’s 2008 presidential vote:

The 26th district in New York gave Barack Obama 46 percent of the vote in 2008. If you follow the Obama vote share along the horizontal axis, you see that a district that gave him 46 percent of the vote in 2008 would, on average, have given its Democratic House candidate under 40 percent of the vote in 2010.

Another way to look at it is this. Here is the Cook Political Report’s Partisan Voting Index for every House district that elected a non-incumbent Democrat in 2010:

Karen Bass, CA-33: D+34
John Carney, DE-AL: D+7
David Cicilline, RI-1: D+13
Hansen Clarke, MI-13: D+31
Colleen Hanabusa, HI-1: D+11
William Keating, MA-10: D+5
Cedric Richmond, LA-2: D+25
Terri Sewell, AL-7: D+18
Frederica Wilson, FL-17: D+34

All this is to say that the most Republican district to elect a new Democrat in 2010 was D+5. New York’s 26th district is R+6. Which is to say, Hochul could not possibly have won this race in 2010, and she probably couldn’t have come close.

Now, quite likely Hochul will be a little dot floating above the trend line—I certainly don’t expect a lot of districts like hers to flip from red to blue in 2012. But I think the race suggests instead that Republicans have taken a share of responsibility for the condition of the economy and Washington. For most of the last two years, Americans have held deeply pessimistic views about economic conditions and the government’s response, and directed virtually all the blame at the Democrats.

Americans are just as likely as before to think things are going badly, but rather than direct all their anger at Democrats, they now have Republicans driving the agenda with a high-profile budget with wildly unpopular priorities. We haven’t returned to a 2006 or 2008 landscape, where the public held Republicans responsible for everything, but the pendulum has swung back. TPM’s track of the Congressional generic ballot bears this out:

You can see that Republicans have lost a year and a half’s worth of gain.

Finally, this was such a nationalized race. Yes, there is a third-party candidate hurting Republican Jane Corwin, and she also made a high profile gaffe by releasing a partial video of her campaign manager confronting him, and then refusing to release the entire version. But Democrat Kathy Hochul is far more popular than Corwin—+17 favorability against -6—so much more so that she’d likely win even without a spoiler. And this doesn’t seem to stem from any special, Scott Brown-ian charisma she’s displayed, nor from any Martha Coakley-esque incompetence on Corwin’s part.

The race has centered almost entirely around the exact theme that Democrats plan to employ in the next election cycle. All this suggests the party has gotten deep traction on the issue, and that the public can react against the policies of the House GOP. The political landscape that produced the Republican sweep of 2010 is gone. Just what replaces it remains to be seen.