Republicans are better at organizing around parsimonious one-liners. These are the "virtues" about which they will not compromise ("if the government would just stop spending money it didn't have;" "seems pretty simple, actually"). These are very effective hubs around which support is rallied -- and these supporters don't necessarily have to understand the full-scale repercussions of their positions because any supposed ill caused in the HERE and NOW is explained away as a painful change for a better tomorrow (for more on this see Povinelli's new book Economies of Abandonment). In this way, these "political virtues" tap into moral ideologies that look a lot like religion or are explicitly religious (see Jazzspazz). Separation between church and State, eh? Protestant work ethic is still the political motto of our era.
Democrats have different affect-laden organizing criteria.