Almost guarantees a Republican Hillary, for starters. It's possible that she'd still become a Democrat, but being in the orbit of such a prominent Republican family I'd bet she doesn't make the switch. I think things, on the whole, would go basically the same as IOTL. George W. still runs for President eventually, Hillary's still First Lady. The only interesting change I see, other than her party affiliation, is where she gains electoral prominence from. Seems unlikely she'd go from Texas to New York for a Senate run, so maybe she stays there. I don't think she'd be as conservative as George, but still more so than IOTL. Who knows, maybe we get Bush-Trump in 2016?