"Marco!" "Rubio!"

I guess we are supposed to be focused on Marco Rubio as the GOP's Great Brown Hope.  The arguments for Rubio are thus:

He's an excellent retail politician.  His disastrous response to the SOTU notwithstanding, he can apparently really nail his stump speech.  He's a "communicator" which seems like a no-brainer for a presidential candidate, but Rubio is apparently pretty adept.

He's young and photogenic.  And Cuban.  He presents a picture of the GOP that is largely at odds with the reality of it.  The GOP is overwhelmingly white, rural and old.  Rubio is none of those things.  If he can convince GOP voters to support him, he can put forth a "new face" of the GOP.

But here are the arguments against him.

He was an apostate on immigration reform.  When the GOP got thumped in 2012, smart Republicans looked at the demographic picture and despaired.  So they decided to move to the center to try and pick off some Hispanic and Asian votes.  Rubio was their standard bearer.  But Washington strategists were out of step with the GOP base, and immigration reform died before the Tea Party's sputtering racism and xenophobia.

Rubio has since move right on immigration, but if that issue becomes a litmus test, it helps Scott Walker and hurts Bush and Rubio.

His fiscal plan is insane.  Now, that hardly distinguishes him from any other GOP candidate, but Rubio is sort of selling himself as the young, Paul-Ryanesque policy wonk.  He's aligned with the Reformicons trying to find a new message for the GOP.

But when your tax plan is as regressive as his, and as fiscally unsound as his...How do you square that circle?  If the press ever starts looking at the details of his plan, he could lose that Reformicon luster.  That opens the door for Walker and Bush, who have been governors.

You can make a good case that Rubio represents the GOP's best hope in 2016.  He's young and somewhat charismatic.  Bush isn't young. Cruz and Walker aren't charismatic.  Rubio moves beyond the stale arguments of a Bush or Clinton restoration.

But it remains to be seen whether GOP voters will support him and whether he truly is ready for prime time.