Majority of responses fall into the 'haven't heard enough' category.
Source: Marquette Law School poll
6/20/2018 update, "Josh Pade leads the parade of unfamiliar Democratic candidates for Wisconsin governor", starts here.
Source: Marquette University Law School poll (June 13-17, 2018)
New Marquette Law School poll finds many Wisconsin primary voters remain undecided, unfamiliar with candidates. (Marquette University Law School poll, 6/20/2018)
Original 6/17/2018 post, "'Undecided' leads in Wisconsin Democrat's choice for governor", starts here.
Democrats determined to be ready for Wisconsin governor nominee. (Wisconsin State Journal, 5/29/2018)
Uncertainty over the nominee has slowed fundraising for Democrats, leading to consternation that they might be in a big hole against Walker by late summer. That prompted Tom Russell, who ran Russ Feingold’s unsuccessful Senate campaign in 2016, to lead an effort for the Democratic Governors Association to raise money earmarked for the eventual nominee.