Angela Alsobrooks gives a campaign speech April 11 at Martin’s Crosswinds in Greenbelt, Md. (Michael S. Williamson/The Washington Post)

Prince George’s County State’s Attorney Angela D. Alsobrooks (D) debuted a television advertisement Thursday, the first in the heated race for county executive.

In the 30-second ad — which will air on cable and broadcast stations in the county — Alsobrooks says residents in the Washington suburb have heard for too long that the county is “on the brink” of success.

“We can give our kids the education they deserve, we can keep our neighborhoods safe, and we can respect the seniors who built this community,” Alsobrooks says. “Let’s fulfill the promises of Prince George’s County together.”

Her campaign declined to say how much the ad cost or which stations it will air on, but said that more ads will run through the June 26 Democratic primary — which, in deep-blue Prince George’s, is tantamount to winning the election.

During a news conference Wednesday, Alsobrooks denounced suggestions by a super PAC backing former congresswoman Donna F. Edwards, her primary rival, that she has participated in “pay-to-play” politics. Alsobrooks called the mailers, sent to Democratic voters in the county, an “evil lie” and said she stands by her record.

Also Thursday, the American Federation of Government Employees endorsed Alsobrooks, citing her “record of following through on her word and getting results.”

The others candidates in the primary are state Sen. C. Anthony Muse, Obama administration official Paul Monteiro, former lieutenant governor Samuel W. Bogley III, Lewis S. Johnson, Billy Bridges, Michael E. Kennedy and Tommie Thompson.