Many readers of this blog would be interested in a series of entries at Mischiefs of Faction on the early results of California’s electoral-system change. The entries are based on lengthier articles in a special issue of the California Journal of Politics and Policy.
From the Mischiefs of Faction summary:
top-two, passed by California voters in 2010 and operating in elections since 2012, creates a two-stage election system that replaces the usual primary-then-general system the state used to have. In the preliminary election (ostensibly a primary), voters may pick from any candidates of any party for each office, regardless of their party registration. The top two vote-getters from that election then go to a November runoff election, even if those candidates are of the same political party.
The findings, as we’ll see, are rather mixed, and what evidence we have that the top-two system has changed politics is pretty modest, at best. Yet as the studies note, it is still early; the new system may be encouraging a new type of candidate to run for office, but it’s just to soon to discern the effects of that.