Unions tend to negotiate for health insurance coverage in the jobs they represent. I understand this is a major issue, and they are very proud of it, but they need to step up and start voicing that they wouldn't have to do this if ALL Americans had access to insurance.
Unions need to go all in with the push for the PO. Maybe they can start running commercials for Rep. Grayson's Medicare for All bill . Commit to buying Medicare for the insurance provider in contract negotiations. Show that this will save money, and the Unions can show they are both pro-labor and pro-business.
Union bashers seem to think that the Unions are anti-business and trying to bleed them dry. The Unions understand without the job, their would be no workers to represent. This would show them to be pro jobs and for a pro jobs environment. If people had medical coverage always available, how many people could leave a current job to start a new business since they are not afraid of losing benefits?
If Unions could convince average people that they are looking out for ALL Americans and not just those they cover (I know the pros of Unionization, I am just saying this is a common mentality, especially among the right), this could have the double impact of pushing healthcare reform and improving the image of Unions in the minds of every American.
They need to fight the two front war of keeping benefits for unionized workers, and fighting for similar benefits to be available to all Americans. When the latter happens, the former will no longer be a large issue