Getting ready to head to New Orleans, I'm a little behind commenting on a few big events in the Southern political landscape, including the announcement last week that nearly 5,000 janitors in Houston had voted to "go union":

Amid yells of "Si se puede" or "Yes it can be done," a group of Houston janitors on Wednesday celebrated their formation of a union, part of one of the largest successful labor organizing efforts in the Texas private sector.

After months of campaigning by the Service Employees International Union, more than 4,700 janitors who work for four of the five largest cleaning companies in Houston agreed to unionize.

Over 5,300 workers will ultimately be represented. As usual, Nathan Newman was one of the few to appreciate the historical importance of this vote:

5000 new members in New York City would be a yawn-- in fact, SEIU has organized far more than 5000 janitors in northern New Jersey in recent years, which is important but not life changing for the labor movement.

But these workers were organized in the South in the private sector, a feat that promises new tactics to support a range of organizing in the region.

The failure to organize the South is the number one, two and three reason why the labor movement peaked after the end of World War II and has been in slow then faster decline ever since. Without unions in the South, it meant that jobs could be shifted more easily out of pro-union areas even for companies that wanted to be in the United States; just look at the Japanese car plants.

I'm a bit more cautious than Nathan about whether or not this signals a major change in the prospects of labor in the South. Our region's history is littered with enthusiastic declarations that "the tide is turning" after particularly successful union campaigns.

But it definitely proves that, even in hostile Southern territory, unions can win. I think one unstated factor in SEIU's victory in Houston was a large and long-standing Latino workforce, which has benefited from progressive political traditions both in the U.S. and across the border.

It's just a matter of time before such traditions catch up in other parts of the South. The fast-changing demographics of states like Georgia, North Carolina and Virginia will also make them fertile territory for worker organizing in the years to come.