Are you better off now?

Why did the Republicans decide to make the question "Are you better off now than you were four years ago?" a central theme to their national convention this year? Isn't this a bit odd, since the economy was in free-fall four years ago, and clearly isn't today? That may be true, but the voters aren't buying it. As I argue in this YouGov piece, voters' four-year retrospection is harsher than their current assessment of the economy. This is true for Romney supporters, Obama supporters, and independents:

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