If Romney wanted to restructure his platform to imitate a popular candidate, seems to me that Cain is in that spot.
Cain hasn’t been able to push Romney because he doesn’t have full support on his own ideas and has shown a readiness to speak out before he gives an issue full though.
In other words, Romney thinks that he can dominate Cain, not the other way around. Romney knows that he is no match for Gingrich, less so Santorum, though I’d match Santorum’s intelligence against Romney any day.