If Trump wins the South Carolina primary, it will be because he expanded his coalition well beyond his blue-collar base—a sign of his campaign’s success and his staying power. Trump isn’t likely to perform as well on the Carolina coast as he does upstate, but if he can tally 25 percent of the vote in wealthy precincts like these, it makes all the difference to his campaign. Without a credible threshold of support from affluent, college-educated voters, he’d probably be running from behind in South Carolina instead of holding a healthy double-digit lead, as most polls suggest.I would expect that the loyal Republican voters, both elected officials and the base voters, will readily support Trump if he's the nominee. And this is a current sign of how that more general acceptance would develop.
Indeed, many of Trump’s most loyal supporters interviewed said they backed Mitt Romney in 2012, even as he badly lost the state to Newt Gingrich. They cited both GOP candidates’ business acumen as reasons for their support, even as their personalities and policy positions diverged greatly.
The importance of rich Republicans to Trump’s success has been overlooked amid his rise to the top of the primary field. The comfortable conventional wisdom, fueled by GOP donor sentiment, is that Trump is fooling less-educated Republicans into buying his current guise of a rock-ribbed conservative stalwart. But based on exit-poll data in New Hampshire and polling in South Carolina, Trump is having stunning success with his own class.
In New Hampshire, exit polls showed Trump won 32 percent of support from college graduates and 31 percent of households making more than $200,000. He won 29 percent of the vote in Bedford, one of the toniest towns in the Granite State. That’s not far behind his overall 36 percent vote in the entire state. In Quinnipiac’s national poll released this week, Trump wins 30 percent of college graduates. That’s still good enough for first place, six points ahead of Marco Rubio. [my emphasis]
But he will have a very difficult time building enough of a following among less dedicated potential supporters to win an Electoral College majority.