The health care industry is trying to stop "Medicare for All." It's alsoa non-starter with Republicans, and some Democrats don't like it either.

But progressives who support single-payer can count on the muscle of onekey constituency: Organized labor.

Bonnie Castillo, the head of National Nurses United, joined POLITICO'sDan Diamond to discuss why her 150,000-member-strong union has thrownits support behind Medicare for All, why she thinks the legislationwould help patients and her members, and how her organization is settingstrategy and viewing the 2020 election.

MENTIONED ON THE SHOW

Activist Ady Barkan, who's testifying at this week's historic Medicarefor All hearing, appeared on "Pulse Check" in December 2017, at anearlier stage of fighting ALS.

National Nurses United helped organize a Medicare for All protestoutside of the headquarters of PhRMA, the drug lobby, on Monday.

Nursing unions have spent years pushing for policy priorities likenurse-to-patient ratios.