While Ted Cruz isn’t Bachmann or Cain, I still don’t think he could win the Presidency unless the Democratic candidate was exceptionally unlikable and weak. Hillary Clinton is neither. Cruz is an asshole, and it takes a lot for Americans to vote for someone like that.
The GOP’s path to winning the White House in 2016 is basically to find another George W Bush. Some outsider who can pledge to “make Washington work again” (aka stop the GOP congressional obstruction), while having the cultural credentials with the GOP base (basically be a Southern Christian) to resist having to constantly placate fears that he’s a RINO, but not so radical that it scares suburban moderates.
This candidate doesn’t exist yet. No congressional Republican can claim they can stop the obstruction (Rubio could try to make the claim if the immigration bill passes, but he’s already been tarred as a RINO, so the racist base doesn’t trust him), and no Governor can meet the other criteria. Chris Christie has already been branded a traitor, and isn’t Southern enough to earn the trust of the base. He would have to spend far too much of the campaign trying to earn their trust and love like Romney did, destroying his credibility with the suburban moderates in swing states. Rick Perry has the credentials with the base, but his anti-abortion crusading has to scare the hell out of moderate voters.
The major question for the 2016 election is the question of race. How many voters wanted to vote for a Democrat, but not President Obama because of his skin color (thereby increasing the votes for Hillary in 2016 automatically), but also how many of the “Obama coalition” (young voters, people of color) will be less motivated to turnout (especially with voting becoming more difficult thanks to the gutting of the Voting Rights Act) and support a non-Obama candidate like Hillary?