Why is Hurricane Katrina and the Gulf Coast recovery an important national issue? There are lots of reasons, but a big one is political.

The failing Gulf Coast recovery, which has kept at least a third of those displaced by Katrina from coming home, has dramatically changed the political map of Louisiana and the South.

The New Orleans Times-Picayune today offers one of the first assessments of the partisan impact of slow-moving Gulf recovery:

A few trends seem certain ... The number of Democrats, both in real numbers and as a percentage of the electorate, is continuing to fall. Registered Democrats make up 53 percent of the voting rolls, down from 57 percent in 2003.

Nearly 79,000 fewer Democrats are registered now than four years ago, while Republicans have gained more than 50,000.

Complicating the picture is that fact that many who haven't returned are still on the voter rolls, meaning the partisan impact will be even larger after the lists are cleaned next year:

A federally regulated cycle of voter roll scrubbing will occur late next year that likely will clear a large number of registrants off the state's list. In 2010 a new census will be conducted, resulting in fresh population figures in 2011 and potentially new political districting in 2012.

In the short term, this will definitely help candidates like GOP gubernatorial hopeful Bobby Jindal and other Louisiana Republicans, who are celebrating their party's good fortunes even as the party struggles nationally.

But there is another trend on the horizon: like other states, Louisiana has been witnessing a steady rise in Latino voters. This was only accelerated by the influx of a new immigrant workforce for post-Katrina rebuilding. The number of Louisiana voters who identify their race as "other" has grown by 15,000 over the last four years, which Louisiana's secretary of state says are largely Latino voters.