January 13, 2012 How much does a VP add to the ticket in their home state?
Answer: at most 4 or 5 percentage points, sometimes less.
Here’s how I looked at it: I looked at how many points a party added in the Vice-Presidential candidate’s home state, compared to their gain/loss in the nation as a whole.
In 2008, the Democratic ticket gained 8 points in Joe Biden’s home state of Delaware (from 53 to 61%), as opposed to 4 points nationally (from 48% to just under 53%). So at most Biden’s presence on the ticket gave the Democrats 4 points in Delaware (8 minus 4).
Similarly, in 2008 the Republican ticket lost only 3 points in Sarah Palin’s home state of Alaska (from 62 to 59 percent) as opposed to 5 points nationally (from just under 51% to 45.6 points). So Palin’s presence on the ticket was worth a couple of points in Alaska.
All of this assumes, of course, that had someone else been on the ticket the parties’ gains and losses in Delaware/Alaska would have been the same as their national gains/losses- which in this case makes sense to me. (By contrast, in 1992 Democrats would have done better in Tennessee no matter who had been Bill Clinton’s running mate, since Clinton was generally more acceptable to southerners than Michael Dukakis).
It seems to me that 2008 reflects the maximum possible gain from a Vice Presidential candidate. Why? Because Delaware and Alaska are two of the nation’s smallest states, and thus the states where voters are most likely to know a candidate fairly well. By contrast, I would suspect that if Sarah Palin had been governor of California (even a fairly popular one) voters would know her less and be less likely to be swayed by her presence on the ticket.