Secretary of Homeland security Janet Napolitano resigned this week, and House Republicans struggle to reconcile the needs of the national party with the desires of their constituents.

Napolitano's departure could offer an opportunity for the Obama administration to make inroads on immigration reform with Republicans. While the bipartisan Senate bill makes heavy concessions toward border security in an effort to win Republican support, many conservatives in the House are skeptical that extra border security will be implemented, despite the assurances of their Senate counterparts.

It is yet another symptom of Republican intransigence over immigration reform. Napolitano has been vilified as an Obama lackey by conservatives, though she has also been attacked from the left for overseeing an increase in deportations and border enforcement.

True border control advocates would be sorry to see Napolitano go, but Obama could potentially nominate a replacement who is even tougher on security, in an effort to mollify Republicans. If Napolitano didn't work for them, it's doubtful anyone could, but that doesn't mean Obama won't try. The lack of an immigration reform bill so far is a stain on his term that he would like to erase.

But House Republicans are beholden to their small districts, not their state or their party. While the Republican establishment wants to make progress with Hispanics in a bid to regain the presidency and become more competitive in swing states like Florida, Nevada and Colorado, that plan will not help representatives from conservative districts.

In fact, supporting any plan that includes a path to citizenship for many of the 11 million undocumented immigrants in the country, as the Senate bill does, will definitely subject many House Republicans to primary challenges from the right. And recent history has shown that those far-right candidates can and do get elected, often on platforms that appeal to emotional concerns and not practical or constructive ones.

At this point, any chance of comprehensive immigration reform depends on small-town Republican legislators and voters putting aside their narrow local desires in favor of national interests. Slim chance.