The Democratic party loves purging its moderates*.
*Dixon was obviously a liberal but when a party is so opposed to compromise, you can be easily labeled a moderate/DINO.
8-)
We've purged way less moderates than you have. Dixon and Lieberman are the only recent examples of purging.
Lieberman was practically begging to lose renomination. He was already collecting signatures for a run as an Independent.
And notable primary challenges aren't always from the left in the Democratic party. See Case against Akaka.
