I really wanted him to come out of the gate the way Trump did when Trump turned (face it, opportunistically) the immigration thing totally into his signature issue. Well, I hoped Walker would expand the concept of what unions were in America, expose them for being Dem money laundering schemes and use them to go after the whole Dem establishment. Hasn't happened, has it?
That is his problem in a nutshell. He is jostling for position, when he needs to be leading. Guys like Trump and Cruz talk about saving America; most of the others focus on out-maneuvering their rivals. As a consequence they come off a bit small. Attacking either Trump or Cruz only emphasizes their problem, it only makes it worse for them.
I notice with a lot of these guys, give them an existential issue and instead of being Churchillian, they start listing senate bills they worked on years ago. They don't get it. People aren't looking for a wonk, they're looking for a warrior.