Well, this is interesting - an AP article on the alarmingly high number of uncontested races for state legislatures. The article explores a number of reasons for the dearth of competition. Not surprisingly, one of them is money: who can afford what Bill Bozarth of Common Cause Georgia terms "the cost to play"? Certainly the way districts are drawn plays into how races are contested - if a district is so heavily weighted in favor of one political party it's thankless work to play the challenger. Then again, a public financing option in the Clean Elections model would encourage more contested primary elections, giving incumbents a run for their money (so to speak) and shaking up what is otherwise a fairly moribund democratic system in a lot of states even in situations where district-drawing is done in a partisan manner.