With Barack Obama preparing a major speech on race for tomorrow, it’s worth taking a step back to put the Jeremiah Wright controversy in a larger perspective.

As TNR’s Michael Crowley reminds us here and here, Obama’s membership in Wright’s church helped demonstrate his cultural authenticity to skeptical constituents in Chicago’s black community. But it’s created a major problem for him now.

The fundamental problem is that the issue positions and cultural affiliations that won elections in Obama’s state legislative district are a relatively poor fit to the presidential election landscape. (They’re arguably a poor fit to the Illinois electoral landscape as well, but the collapse of Obama’s primary and general election rivals in 2004 let him skate into the Senate without coming under serious criticism.) The fact that he has done so well in the presidential race despite the mismatch is a testament to what a remarkably gifted politician he is.

The genesis of this argument is my friend and co-author Michael Tofias, who has a working paper (PDF) showing that “members of the House are more likely to run for the Senate when their districts have high congruity to their prospective statewide constituency.” This constituency fit problem is a reason why it’s so difficult for black elected officials to win statewide (or national) office — many of them represent heavily minority constituencies (often the result of racial gerrymandering) that are quite different from the ones they would represent higher up the ladder.

Obama may be able to move past the Wright problem in the near term, but these sorts of controversies will come up again and again on other mismatch issues like gun control and the death penalty.

Update 3/18 8:22 AM: Commenter Rob notes that Matthew Yglesias made the same point as Crowley:

Obama’s going to have a hard time explaining that I take to be the truth, namely that his relationship with Trinity has been a bit cynical from the beginning. After all, before Obama was a half-black guy running in a mostly white country he was a half-white guy running in a mostly black neighborhood. At that time, associating with a very large, influential, local church with black nationalist overtones was a clear political asset… Since emerging onto a larger stage, it’s been the reverse and Obama’s consistently sought to distance himself from Wright, disinviting him from his campaign’s launch, analogizing him to a crazy uncle who you love but don’t listen to, etc.