If Hillary won, why wouldn't the Senate just confirm Garland before she takes office?
They would have just spend a whole year saying the president shouldn't get to choose the Supreme Court member in his final year in office.
You think McConnell cares much about that? Yeah, it's why they won't confirm Garland before the election no matter how much Trump trails, as it could easily backfire, but if and after Hillary wins and takes the senate, I could easily see them deciding they can't risk a more liberal nominee and therefore elect to approve Garland while they have the chance.