AT&T just flooded the coffers at Locast, a free streaming service for local broadcast television, with a $500,000 donation to help fuel the service’s expansion to more markets.

The donation was made to non-profit advocacy group Sports Fans Coalition NY, which operates Locast. The service is currently available to more than 32 million users in 13 cities – New York, Chicago, Los Angeles, San Francisco, Philadelphia, Dallas, Washington, Houston, Boston, Denver, Baltimore, and Rapid City and Sioux Falls in South Dakota. The company said it reaches nearly a third of all U.S. TV homes.

A Locast representative declined to comment on the donation. In a news release, AT&T said that the donation is meant to support Locast’s “mission to make free broadcast content available to consumers and offer them more choice.”

RELATED: AT&T integrates free broadcast TV app Locast on DirecTV, U-verse

About one month ago, AT&T announced that it is integrating Locast’s service on its pay TV platforms, DirecTV and U-verse.

“AT&T continues to offer consumers new ways to access the video content they want. We believe Locast's public service offering will make sense for many of them,” AT&T wrote in a news release.

The integration, coupled with the new donation, could be viewed as a move by AT&T to gain more leverage in carriage negotiations with broadcasters and television station groups. If stations go dark on either U-verse or DirecTV due to impasses over retransmission consent agreements, AT&T can point to Locast as another option for allowing its subscribers to continue receiving local broadcast channels.

For Locast, the donation represents a major shot in the arm. Locast is a free service that streams full-power broadcast channels in a local markets to anyone with an Internet connection located within the relevant Nielsen Designated Market Area (DMA). Locast’s operational costs do not include licensing fees paid to broadcasters. The organization relies on a statute within the Copyright Act that allows a non-profit organization to retransmit local broadcast signals.

But, Locast does ask for donations to help it reach its goal of nationwide coverage.

“...Our biggest obstacle is funding,” said David Goodfriend, chairman of Sports Fans Coalition NY, in a statement. “Locast is asking each user to contribute $5 per month, which the organization said would make it fully sustainable and capable of reaching all 210 U.S. television markets.”