I never understood his appeal. Other than his union busting...he just didn't seem to offer much. I suspect it helps the right wingers for the early primaries. Carson? Cruz? Long term it probably helps the less nutty -- just lessens the noise for the remaining candidates. One less distraction.
My guess is Walker stood no chance if nominated to win his own state. He had said before that hundreds of thousands protested him at the state Capitol. Isn't that like more than half the population of Wisconsin?
At the time he dropped out, Walker was polling at < 2%, even <1% in one poll. So, as a short term matter, I doubt that him dropping out adds much to anyone's numbers. The main "resources" that may be re-allocated from Walker are the donors and their cash. Walker had $20M in Super PAC money when he dropped out, and perhaps more support coming from the likes of the Koch Brothers if he stayed in the fight. Now these guys have to find an outlet for their cash.
Rand could be the next to pull out. He is down there around the 1-2%. However, I suppose Walker dropping out could help Rand with the union busting crowd. The Kochs like those positions and also the flat tax to lower their taxes, but most of the other Repubs like those positions, too.
Not surprising in the least. He looked totally and completely disinterested in the debate last week, even though it was a lot of HIS ideas that were being discussed. Oh well, good riddance.
Walker was perhaps the Koch Brother's main boy. Interestingly Walker then urged others to drop out. Maybe this was prompted by the Kochs. Perhaps they have decided that Trump is a threat since he has said such heretical things (in their minds) as taxes maybe should raised on the wealthy. I'm not sure but Trump may not be enough of a climate change denier for the Kochs and their small network of mega wealthy donors. Trump, of course, is a pain for the Kochs since he is not as dependent on their money as many of the rest will be.
Interesting article about who Trump stole supporters from and the demographic of this supporters: http://www.newsweek.com/who-are-trumps-supporters-hard-stats-373560. It looks like Walker was hurt the most by Trump's success.