“Every people should be left free to determine its own policy, its own way of development, unhindered, unthreatened, unafraid, the little along with the great and powerful… These are American principles.”
Woodrow Wilson

Every ten years a census is taken of the United States. The number of members of the House of Representatives from each state can change based on that census since the representatives are aligned with the populace. That is why a state like California, New York or Texas can have so much power. After the census, each state has the opportunity to redraw voting districts based on population shifts, however most of these shifts appear to be decided by the political party in power at the time. I fear that Louisiana will be carved up in some bizarre fashion after the next census since o many voters moved out of state after hurricane Katrina and never returned.

Pretty timely for us in the U.S. :)