Well, the Republicans haven't been quiet, but you have to rely on the media to report what they are saying and they don't believe that anything a Republican says is front page news. Here are the few articles I could find
Maine Repubs Say No to Chavez Oil Deal
http://www.chron.com/disp/story.mpl/ap/fn/4205201.html
Chavez Slammed For 'Devil' Remarks
http://wcbstv.com/topstories/topstories_story_264175815.html
GOP blasts Harkin comments on Chavez
http://desmoinesregister.com/apps/pbcs.dll/article?AID=/20060921/NEWS/60921028/1001/NIE
Under an agreement last winter, Citgo, the Houston-based subsidiary of Venezuela's state-owned oil company, was to sell 8 million gallons of heating oil on the open market and donate what amounts to a 40 percent discount to Maine. It also donated 120,000 gallons of oil to 40 Maine homeless shelters.
http://www.chron.com/disp/story.mpl/ap/fn/4205201.html