Here's a pretty good piece on the shape of the GOP race, by Steve Hayes, in the Weekly Standard. Of course, Steve Hayes is in the neo-con camp himself and pretty clearly favors Rubio, but this a balanced piece and he is knowledgeable on the subject:
http://www.weeklystandard.com/the-real-shape-of-the-race/article/2000939
This section is insightful:
"To be sure, Cruz and Rubio are running for president in very different ways—though both are familiar. Rubio is campaigning like Barack Obama did in 2008. He has chosen to emphasize optimism, unity, possibility, reform. He defends his decision to run as a young candidate by emphasizing the "urgency" of the problems facing the country, just as Obama cited Martin Luther King Jr.'s "fierce urgency of now" for his audacious first run for the presidency. There's a lot of tough criticism of Obama and Washington in Rubio's stump speech, but there's also a lot of "hope and change."
Cruz is running like Obama, too—Obama in 2012. He is campaigning as an unapologetic ideologue, seeking to motivate and energize conservatives unenthusiastic about recent Republican nominees. Cruz's campaign, like Obama's reelection effort, is based on the assumption that the contest this fall will be won by the candidate who best turns out the base of his or her party.
These distinct approaches in campaign style have doubtless added to the perception that Rubio is an "establishment" candidate and Cruz is "anti-establishment." But the real difference between them isn't
whether they would challenge the Republican establishment but
how. Rubio's critique of the establishment is a temporal one, argues Heritage Action CEO Michael Needham. In Rubio's view, the ideas of the Republican establishment, stale and anachronistic, are badly in need of replacing. So Rubio champions policy innovation and creativity.
Cruz's critique of the GOP establishment is structural. Republican institutions in Washington have become so badly corrupted that trying to reform them isn't enough. Needham summarizes the Cruz view this way. "Real policy innovation requires not just putting forth fresh ideas; it requires attacking the flawed nature of the GOP establishment so that innovation can even be possible."
They're both right.
There are reasons a conservative voter might prefer Cruz to Rubio. Cruz has demonstrated a willingness to challenge the calcified structures of the establishment and to continue doing so despite scorn heaped on him not only from the
New York Times but also from fellow Republicans. It's a necessary quality for a president who would serve as a disrupter of the broken status quo in Washington. Rubio may have it, and in his advocacy of entitlement reform we've seen hints of it. But with Cruz, we know.
There are reasons a conservative voter might prefer Rubio to Cruz. Rubio has a personal appeal—likability—Cruz lacks. When Cruz addresses voters, he's often self-indulgent and always melodramatic. He speaks as if he's there to bestow knowledge on the audience, and he's frequently the hero of his own story. Rubio is nearly the opposite. When he speaks, there's a genuine sense that he's in awe of the country and his place in it. His paeans to American greatness seem heartfelt even the twentieth time you've heard them. All of this would seem to make him more electable in the general election.
Regardless, if either Cruz or Rubio is sworn in on January 20, 2017, the country will have its most conservative president since Ronald Reagan."