The Koch's are Libertarian, that is NOT Conservative.  Although the two ideologies do have some common denominators, but they are NOT the same.  The writer is clearly uninformed.
As a matter of fact, the Republican name tag does not necessarily mean Conservative. Republican is a party, Conservative is an ideology, the two can be joined, but not always.  Susan Collins of Maine is a prime example of having an R name tag and NOT being conservative. She still holds that seat in left leaning Maine.