Paternal Grandparents - hardcore union Democrats dating back forever, never voted for a Republican President, generally socially conservative (pro-life, maybe "not my business" on marriage but still sometimes say offensive things about gay people and other minorities)
Maternal Grandparents - Rockefeller Republicans, voted for a few Democratic Presidents when the time was right (Kennedy, Johnson, Clinton), tacitly racist (it's a generational thing) and pro-life but pro-gay marriage, conservative enough to appeal to most of the party but would be disliked by the base because "establishment"
I imagine some sort of progressive third party would emerge, as richer liberals would be disillusioned. The Bay Area, Seattle, and the Northeast would not like the Dems because of their social conservatism but the Republicans are not moderate enough for liberals to climb aboard. Assuming that these are the only two tickets on the ballot, though...
