Let's save some venom for Hillary, ok?
Seriously, right now none of the Republican candidates are polling above 50% (not even Trump). That means that whichever candidate you are supporting, he is going to have to change the minds of some non-supporters to get the nomination. He is then going to have to win the support of most or all of the remainder of his non-supporters to beat Hillary.
You do not win over supporters by attacking them. Have any bitter conservatives out there been convinced to stop clinging to their guns and religion because of Obama's non-stop attacks?