Politics: Sen. Mary Landrieu was the new "Louisiana Purchase." Sen. Ben Nelson got the federal government to pick up his state's future Medicaid tab. Maybe we should just put Senate votes up on eBay. Nelson, the 60th vote in the middle-of-the-night Senate party line vote on health care reform, will go down in American political history as the inventor of the permanent earmark. His seemingly principled stand against including federal funding for