Radio host Mark Levin has fired a Dec. 8 warning shot at Sen. Marco Rubio as he escalates his campaign-trail criticism of rival Sen. Ted Cruz.

I was among the first national radio hosts to support Marco Rubio in his uphill Republican primary campaign for the Senate against the unprincipled Florida Governor Charlie Crist. Back then, he ran as an unabashed Tea Party conservative. I also supported Mike Lee and Ted Cruz, among others, in their campaigns against the entrenched GOP establishment.

But soon after arriving in Washington, Rubio decided to throw in with these politicians – including John McCain and Lindsey Graham and take an active leadership role in the Gang of Eight fiasco. As he runs for the Republican presidential nomination, Rubio has attempted to redefine his position on immigration yet again, resulting in his utter incoherence on the subject.

Moreover, Rubio’s views on foreign policy are also more in line with McCain-Graham pseudo-conservativism. It is a kind of naïve and radical interventionism, involving endless demands for American ground forces, that President Ronald Reagan would never have supported – and did not…

This is a friendly warning to Marco Rubio and his campaign donors, advisers, and consultants that they cannot wash away some of Rubio’s less than stellar legislative actions and related positions and pronouncements by embracing and unleashing Saul Alinsky-type tactics against Ted Cruz or other conservatives. Such unprincipled ambition has not and will not go unnoticed by conservatives.

Rather than proudly standing on his own record, and contrasting his positions honestly with those of Cruz, the latter of whom is clearly the more conservative and anti-establishment candidate, Rubio and his surrogates have launched a propaganda campaign against Cruz in a deceitful attempt to distort his record…

I will stop here. Marco Rubio is a talented man who can potentially contribute a lot to this presidential race in the remaining months. But that will only happen if he abandons his Alinsky tactics for a more Reaganesque approach and treats the conservative electorate with the respect it deserves. If Rubio is proud of his record, then he should defend it. If he objects to Cruz’s record, he should challenge it. But stop falsifying both.