I'm part of the 27% of registered Republicans who voted for Haley yesterday. I voted for her because I think she is truly the best candidate in the remaining pool, has the best chance of winning the general election, and I sincerely hope that she can be the (R) nominee in November. No ulterior motives.
Anecdotal, but within my circle of friends and business partners in the state, about 3/4 voted Haley and the last 1/4 Trump. It's an impression and certainly not a science we can apply onto the broader electorate, but I would wager at least half of those who voted Haley yesterday will not vote for Trump in the general if he is the nominee. They will vote third party or not vote at all.
For many Republicans in the northeast, Trump has lost all luster and is not a viable candidate. The northeast is certainly not representative of the rest of the country (one could argue a Republican vote in New England doesn't really matter since the states have little hope of voting red in the general any way), but that lack of enthusiasm from blue state Republicans and independents portends calamity for (R)s in November. I fear deep down the Trump campaign understands this (though it might not be acknowledged), but they simply do not care. Like last time, the loss will not be treated as a loss. There will be no accountability. It will be branded a steal. Rinse, repeat.