Because I guess they think that Arkansas is a waste of money, for whatever reason. Either that, or they're just not real supportive of truly conservative candidates. That seems plausible, too. I'm sure that real conservatives are as much of a PITA for RINOs to work with as RATs are.
In Michigan the trend is Democrat (&%*%$#@), not like NY or Caleefornia, but hard to overcome the Union voter turnout stuff.