Washington has been chewing over election-related numbers for three straight days now, and I’d like to highlight one particular set of data that’s probably giving Karl Rove a nasty case of indigestion: the effect of the immigration debate on the midterm results.

A few months ago, most House Republicans thought that border security would be, as Rep. Jeff Flake put it to me, their “magic carpet ride” to re-election. Moderate and pro-business elements within the party tried to convince them that a hard-line stance a) wouldn’t actually deliver that many votes, and b) would incinerate Karl Rove’s efforts to weld Latinos to a long-term Republican majority. And on both counts (as we anticipated in October) they were right.

Nearly every Republican who ran primarily on an enforcement-only platform lost. Of 15 congressional or gubernatorial races where immigration was a major issue, Democrats won 12. Even worse for Republicans, the hard-won gains made by Rove, Mehlman and Bush with Hispanic voters in 2000, 2002 and 2004 were essentially obliterated. Voting in presidential-race proportions, Latinos supported Democrats over Republicans in House races by 69-30. In Western House races, Latinos comprised 16 percent of the voters (compared to 8.5 percent nationally), and voted for Democrats in even higher proportions: 72-27, according to CNN’s exit poll.

So far, the buzz about the Hispanic vote has focused on the role immigration played in driving Latinos away from the GOP. Democrats mostly allowed Republicans to shoot themselves in the foot on this one, so you could be forgiven for thinking that they simply benefited from the misguided antics of an inflamed conservative base. But that interpretation repeats a mistake both parties have made at various times: viewing Latinos as a convenient voting bloc that can be easily manipulated without real political investment. Democrats made that mistake by not paying enough attention to the complex concerns of Latino voters in recent elections. Rove and Mehlman made it by thinking that all you need to do to lock up Latino support is run soft-focus ads about the American Dream and have the President give periodic speeches about a guest worker program, without trying very hard to actually implement one.

The reality is more complicated. It’s a quirk of the Hispanic vote that political parties don’t necessarily win Latinos with immigration policy—it’s rarely the primary factor in their voting preferences—but can easily lose Latino voters with policies that appear excessively punitive towards immigrants (which is what happened in California in the 1990s). After all, right before the election, Latinos ranked Iraq and the economy as their overriding concerns. Yesterday, NDN held a panel to read the post-election tea leaves, where an interesting point was raised: Democrats made raising the minimum wage a centerpiece of an aggressive Spanish-language advertising campaign this year, especially in Colorado and Arizona. I don’t have any hard data to support this, but I wouldn’t be surprised if Democratic gains among Latinos turned out to be a complex mix of dissatisfaction with the war, alienation from a GOP gone nativist, and, at least in some cases, receptiveness to a substantive Democratic policy proposal that directly affects many Hispanic families. (Latinos comprise nearly 20 percent of the workers who would benefit from a minimum-wage increase). Whether or not this turns out to be the case, those Democrats who actually engaged with a real concern of many Latinos took a smart step in the right direction this year.