The Republican callers are really rats.
It's so transparent.
Convincing people they're disgruntled Republicans is a huge part of the Rats' strategy. They do it when the seminar callers call talk radio, their seminar posters do it here, they do it with their letters to the editors, they do it with polling.
They think if they can manufacture the illusion a bi-partisan anti-war/anti-Bush majority, the rest of the sheep will follow suit and join them.
It's pathetic, but somewhat effective. Especially with middle-of-the-road moderates, last minutes swing voters and other morons.