Here is one basic link I have recovered, I know there are others out there since this is a new one to me.
USATODAY.com - Has Citgo become a political tool for Hugo Chvez?
Another link found, not as much info, but in line with what I am remembering.
Will Citgo suffer Chavez backlash? - U.S. business - MSNBC.com
Right now most of what I am finding are groups bashing and calling out of the boycott. Sorry I dont have the actual news link I refered to, but hope this gives you an idea of what I meant.