By Kalani Leifer Opinions Columnist Friday, May 13, 2005 last updated May 12, 2005 7:58 PM In the spirit of one of Stanford's most enduring and productive traditions, White Plaza has once again become the stage for political demonstration. Don't worry, though, you won't find anything controversial like mock same-sex marriages or miniature anti-abortion cemeteries. And while the present display of youthful involvement is being staged by a partisan organization -- the Stanford Democrats -- it should by all means be a bipartisan endeavor. One of the U.S. Senate's own most enduring and productive traditions, the filibuster, is in danger...