It’s “do-or-die” for Nikki Haley in South Carolina — but for MSNBC’s Chris Hayes the GOP nomination race is Trump’s to lose either by a legal loss or a hit to his health. In an op-ed titled “How a key failing in Republican politics turned Trump into the de-facto nominee,” Hayes says he believes South Carolina, despite being Haley’s home state where she served as governor, will prove to be a “very uphill battle” for her. “Trump has looked like the de facto nominee for so long that political junkies and neophytes alike might be forgiven for viewing the aspirations of replacing him as the leader …