Haunted by memories of the failed effort to revamp health care during the Clinton administration, some nonprofit groups this summer are taking a more aggressive approach to pushing their ideas for a health-care overhaul.

But do nonprofit groups and foundations have the clout — and the money — to make a difference in the high-stakes battle over the future of America’s health-care system?

The membership organization AARP believes it does. With 40 million members, AARP is using its size and influence to help lead efforts to support health-care legislation that would benefit its far-flung membership.

To learn more about what the organization hopes to accomplish, listen to The Chronicle’s latest edition of Philanthropy This Week, a podcast about and for the nonprofit world.