"More extreme than Hillary and Kucinich: Among the White House wannabes, long-shot Rep. Dennis Kucinich has the reputation of holding the most left-wing congressional voting record. In fact, this ?honor? goes to Kerry.
According to American Conservative Union, Kerry has a lifetime rating of 6 percent, compared to 13 for the demolished Rep. Dick Gephardt, 14 for Sen. John Edwards, 15 for Kucinich and 19 for Sen. Joe Lieberman.
Sens. Hillary Clinton and Tom Daschle score 13 percent. Only the likes of Sens. Teddy Kennedy and Barbara Boxer have more left-wing records than Kerry. In contrast, Sen. John Breaux, one of the upper chamber?s few remaining moderate Democrats, has a 46."
According to the non-partisan ranking system Kerry is the 11th most liberal senator. His votes are more liberal than Hilary, but I didn't see anything on Kusinch since he is on the house.
Here is an interesting article that provides a more detailed explanation of the rating system and the thinking behind it.
http://nationaljournal.com/about/njweekly/stories/2004/0830nj_liberalratings.htm 
