Nate Cohn rebuts various pundits who argue otherwise:

It was frequently observed that a Romney victory would have required a historic performance among white voters, provided that Obama could match his ’08 performance among non-white voters. Bush’s 2004 performance among white voters wouldn’t get it done anymore. In 2016, the math gets even more challenging. If the white share of the electorate declines further, Republicans won’t just need to match their best performance of the last 24 years among white voters, they’ll also need to match their best performance of the last 24 years among non-white voters. If they can’t make the requisite 16-point gain among non-white voters—a tall order, to say the least—then the next Republican candidate will enter truly uncharted territory, potentially needing to win up to 64 percent of the white vote just to break 50 percent of the popular vote.