A couple of weeks ago, reflecting on the state of the race, I said:

My feeling at the end of the two conventions is that the Republicans had utterly failed to make a case for their party or their candidate, while the Democrats had largely succeeded in making the case for their party – spectacularly so with Bill Clinton’s speech – but had done a more equivocal job of making the case for their candidate (particularly because, after being lauded as a man of steel completely focused on the needs of the middle class, he came off in his own speech as something rather different).

As I’ve observed the race since then, I have only become more convinced that what has changed the dynamics of this election has been a fundamental reevaluation not merely – or even primarily – of the two candidates, but of the two parties. This election is becoming nationalized, and it is becoming nationalized in the context of an across-the-board swing in the direction of the Democrats.

The reason, I think, is a simple one. The Republicans Party – not just the Romney campaign, but the party as a whole – is running on nothing. They are running on the presumption that the country has already rejected the Democrats, and that therefore it is their turn. They are behaving as if choosing Democratic governance was some kind of “experiment” that didn’t work out, and now the American people will, of course, come back to their natural home.

By contrast, the Democrats actually made a case for their party. They explained what their party has done, and why they should be able to set the national agenda. They defended their foreign policy, their economic policy, and their social policy in strong, unapologetic terms.

Obviously, if you already strongly disagree with those policies, you weren’t likely to be convinced. But if you are inclined to agree with them, the experience of the convention must have been energizing. And if you have diffuse or muddled opinions, the contrast in approach was hard to miss.

What I was looking for, two weeks ago, was a sign that a broad partisan shift was happening. Here’s what I said:

[I]f the conventions really have moved the polls permanently, they may have moved the partisan needle, and not just Obama’s favorability. Rationally, voters who trust Obama personally, but are skeptical of his policies, might be inclined to ticket split. But if voters have formed an impression that they trust the Democrats more than the Republicans, then ticket-splitting is not rational. If the generic Congressional numbers move with the Presidential race numbers, we’ll have some indication that it’s the latter and not the former.

What has happened since then is exactly what I was anticipating. The generic Congressional ballot has shifted in the Democrats’ direction, to a 2-point lead according to the RCP average. More strikingly, a number of Senate races have shifted sharply in the Democrats’ direction, from Wisconsin to Massachusetts to Virginia. I picked these three races in particular, because they are races not races where “candidate quality” is a plausible cause of Republican troubles (as in, say, Missouri). Scott Brown is a highly popular Senator. Tommy Thompson is a highly popular former Governor. George Allen is, if not highly popular, nonetheless a former Senator. One of them is an incumbent; none of them are running against incumbents. If they lose their elections, it won’t be because they are personally unpopular, or because they just couldn’t overcome the popularity of their opponents, or because they are individually out of ideological step with their constituents. If they lose their elections, it will be because they have an “R” next to their names.

Of course, there’s plenty of time for additional turns of the screw. And we haven’t seen recent polling from deep-red states like North Dakota or Nebraska, and very little from Nevada or Montana. We’ll see whether, when that polling comes in, it confirms the trend or complicates it, not to mention whether the Democratic advantage in the generic Congressional poll extends or reverses itself.

But for right now, what we’re seeing, I believe, is a rejection not merely of Mitt Romney and his inept campaign, but of the Republican Party as it has chosen to represent itself in this election. And I suspect it is too late to reverse that judgment – the best the GOP can hope for is that something catalyzes American distrust of Democrats to match.

I’ve been saying this from the beginning of the campaign, and I stand by it. Mitt Romney is a lousy candidate – tin-eared, brittle, easily-bullied, someone basically nobody thinks of as a natural leader. But he is not the fundamental problem. The fundamental problem is the party he is leading.