So far, the only anti-Hillary movement I see is Donald Trump. Who the Republican party seems to dislike.
Actually majority of REPUBLICANS favor Trump. It is the party elites and career politicians who dislike Trump, because the donor class loses control over their agenda with Trump.
The GOP establishment hates Trump and Cruz equally. Cruz has been a major pain in their behind since he got elected to the Senate. He made the GOPe pay a political price for every betrayal of conservatives, and there were a lot of them. It was Cruz who opened the curtains of politics and showed exactly how the GOPe works with Democrats and tries at the same time fake it as if they are fighting for conservative principles.
To the extent that Huckabee and Santorum throw their support behind Rubio, they will show once and for all that they are proud carrying members of the GOPe, and that they therefore have joined with the betrayers of social conservatives.
They were all ready to unite against Cruz during the primary. They never saw Trump coming. While Trump did not fight the GOPe for years, he is definitely not part of their cozy club. He therefore is as hard to control as Cruz. Trump has not directly challenged the GOPe as Cruz does, but his very existence threatens the GOPe.