The phrase "collar jobs" refers to jobs that require skilled or professional work, often involving office or administrative tasks. These jobs typically do not involve physical labor, but instead involve mental or knowledge-based work.
And importantly, the ad stated their intention to try and help women in blue collar jobs where it's even harder to speak up against sexual assault. (aliciamalone.com)
Public investment will be needed for things like mass transit and green collar job training, but there are other revenue sources for these. (dotearth.blogs.nytimes.com)