That's the thing, many of his voters DO think he would veer our country in a better direction. Some of them don't think the changes he proposed would have a negative impact on them. In fact some viewed it as a benefit. It is the mentality, "as long as I am ok and things could potentially be better for me, who cares if it is not for others. Not my problem." Also many of his voters did it solely out of hatred such as they dislike Hillary, Obama, Liberals, Democrats, etc. Then there are his devoted fans who would support him regardless; those who voted for him just b/c they can; those with resentment towards the government (or anti-government) so it was their way of saying "Fuck you!" Not to mention most Republicans having been voting against their financial prosperity and overall well-being for quite awhile now.
He didn't get a lot of support from his party when he ran recently so I don't think having a lack of support from other Republicans would matter if he does decide to run for a second term. Like I said, if he plays his cards right this term by fulfilling a few of his promises, he could win a second term.