WASHINGTON — Supporters of the 2010 health care law will launch a political coalition today to block its repeal. They’re targeting Republican lawmakers whose constituents may now be at risk of losing health insurance.

The initial goal is to stop Congress from repealing the law without simultaneously passing a replacement for some 20 million people covered through subsidized private health insurance and expanded Medicaid.

Called “Protect Our Care,” the group brings together organizations that helped pass the Affordable Care Act, also known as “ObamaCare.”

On the list are the NAACP, advocacy groups like Families USA and the Center on Budget and Policy Priorities, the Service Employees International Union, which represents many health care workers, and the Center for American Progress, a think tank closely aligned with the Obama White House.

Coordinating the group’s activities will be Leslie Dach, a former Wal-Mart lobbyist who served as a top adviser to Health and Human Services Secretary Sylvia Burwell in the Obama administration.

“Repeal and Delay is no better than repeal. American families deserve to know what will happen to them before Congress acts,” the coalition said in a statement.