David Schleicher has an awesome article on the problems with using national party brands in local elections. This piece and his paper with Chris Elmendorf are well worth your time:
But the veneration of local politics is based on a basic misunderstanding of how voters behave. For all the flak that national elections get, they have real meaning. Voters are presented with a clear choice between candidates from two very different and competitive parties, whose contrasting positions on key issues makes the decision about which party and candidate to support relatively easy for most. State and local elections look very different. Battles for control of legislatures are frequently uncompetitive, parties regularly do not take stances on key issues, and voters are poorly informed about the issues at stake and would struggle to pick most candidates out of a lineup.
What often ends up happening in state and local elections is that a voter casts a ballot for a candidate from the party whose national stances she agrees with. For all the paeans one hears to “our federalism” from politicians and judges, the paradoxical truth is that voters do not actually know more about elections and issues in their backyards. They know less.
When you think about it, this makes sense. We are too busy and the individual benefits are too small for most of us to invest time and effort in learning much about issues or candidates for county legislature or even Congress before we vote. In order for elections to be meaningful, we need help.
In federal elections, party labels provide us with that help. Particularly in these polarized times, knowing that a congressional candidate is a Democrat or Republicans tells us almost everything we need to know about how she’ll vote in Congress. Furthermore, because the parties are pretty consistent over time, we can develop “running tallies” of observations about what Democrats and Republicans have done while in office that can guide us in the voting booth. As long as some people notice each political event, the electorate as a whole can develop “macropartisan” running tallies that shift in response to the successes and failures of each party, and an uninformed electorate can behave like a more informed one. Not perfectly — the electorate can be myopic, influenced by irrelevant information and biased in how it interprets data — but better than you would think if you only looked at survey data that shows that many Americans know little about politics. As a result, federal officials can be held somewhat accountable for their actions. If the economy is doing badly or the government does something unpopular, the party in power will have to pay a political price.
In state and local elections, we rely on party labels too, but they do less work for us. The reason is that even when the election is for local office, we still rely on national party labels. There is a “mismatch” between the level at which party identification is created and the level of government at issue in the election.