If Democrats end up winning big next week, not only at the presidential but the congressional level, to what extent will it represent an endorsement of the party's ideas? That would be the major question going forward. And those who oppose the Democratic agenda will, almost certainly, argue that Democratic themes and policy proposals had nothing to do with it. 

The claim will have at least some truth. Lots of people vote on personality or parochial loyalties. And even those thinking more substantively will frequently make their decisions based on gut reactions to the Bush era, rather than deep thoughts on whether, say, they like the idea of a cap-and-trade scheme.

Still, ideas matter. And one way to tell is to consider the rhetoric Republicans themselves are deploying right now. Here's one random, but convenient, example:

Last week in Michigan, I heard a radio advertisement from Representative Candice Miller, an incumbent three-term Republican who represents parts of Macomb County and some nearby communities north of Detroit. The focus of the advertisement was her policies on energy independence, which isn't wholly surprising given the frustration with high gas prices.

But what struck me was the appeal's phrasing and emphasis. Two-thirds of it was spent bashing oil companies for excessive profits, in no uncertain terms. Support for more domestic drilling followed, although it was couched very carefully so as not to sound too unfriendly to the environment. (Sorry I don't have exact words. I was driving so I couldn't take notes.)

I'm hardly an expert on Miller's career. My quick googling and search of newspaper archives reveals that, in fact, she did make some pretty harsh statements about oil companies earlier this year--and voted, against her party, to take away some oil company tax breaks. I have no reason to think the ad doesn't represent her views accurately.

Still, my (again, cursory) research also suggests she's a very pro-business business Republican, with sky-high voter ratings from all the business interests.

Miller's distrcit was the result of Republican-friendly redistricting after 2000. And, from what I gather, she's in no serious danger of losing her seat this year. But she appears to have aspirations for statewide office. (Her name has come up before in conversations about running for either governor or U.S. senator.)  The fact that Miller is running ads that sound like Al Gore's infamous "people versus the powerful" message tells me that she and her strategists think liberal popluism will help her succeed politically.

My bet is that Republican candidates elsewhere are also running on Democratic-sounding themes. (Readers, feel free to submit examples in the comments.) If so, that's worth remembering in a few weeks.

Update: Of course, as my colleague Eve Fairbanks notes, sometimes Democrats sound like Republicans, too. But that's happening in Southern, conservative districts.

--Jonathan Cohn