The first poll is out on the conflict between Walker and the unions. It reflects something, but not the thing that counts: Wisconsin public opinion.
A new Rasmussen Reports national telephone survey finds that 48% of Likely U.S. Voters agree more with the Republican governor in his dispute with union workers. Thirty-eight percent (38%) agree more with the unionized public employees, while 14% are undecided.
First point: I do not consider Rasmussen a trusted source on this particular poll. I do trust Rasmussen campaign polls because, despite its Republican ties, the company cannot afford to put out polls that diverge wildly from election results. However, when surveying public opinion on issues, Rasmussen has considerably more wiggle room. And it has a well-documented history of bias for conservative responses.
More importantly, this poll doesn't show the effect the protests have had on the people they are intended to sway: Wisconsin voters. Until we get a Wisconsin-specific poll, there's no way for us to know how likely it is that the protests could sway GOP senators.