Andrea Peyser

Andrea Peyser

US News

The gall of those Kennedy gals!

When it comes to middle-aged sex and betrayal, women with Kennedy blood in their veins give as good as they get.

For years, Maria Shriver, 58, who last year signed on as an NBC “special anchor’’ after a nearly decade-long break from the tube, played the victim. She presented herself as the long-suffering wife of actor-turned-politician-turned-actor Arnold Schwarzenegger, 67. California’s Austrian-born then-governor admitted publicly in 2011 that he fathered a love child, now 16, with the family’s housekeeper, Mildred Baena, now 53 — a boy who was born just five days after Shriver gave birth to his half-brother.

Shock! Scandal!

Now it seems that as the sparks fizzled between the Sperminator and the household help, Shriver, the mother of four of Schwarzenegger’s children, allegedly carried on a years-long illicit affair with another underling, Schwarzenegger’s twice-divorced former lead campaign strategist, Matthew Dowd, 53, who now works as an analyst for ABC News, The Post’s Tara Palmeri reported.

Shriver went public with Dowd Aug. 2, taking him to the Massachusetts wedding of her environmentalist cousin Robert F. Kennedy Jr., 60, and actress Cheryl Hines, 48. But campaign staffers and other sources told Palmeri that their fling began back in 2006, as Schwarzenegger ran for re-election as governor.

Schwarzenegger found out and it was “total chaos,’’ said a campaign staffer, who recalled yelling and crying matches between California’s first couple. Dowd was banished from the suite in which the Republican governor gathered with other strategists on the night of his 2006 re-election. A source said Shriver flew to New York in 2007, staying at the Four Seasons Hotel and seeing Dowd, and met him in Santa Monica, Calif., while Schwarzenegger was in the state capital of Sacramento.

“Maria likes to make it appear that she’s the victim, but she’s not,’’ said a source. “The [idea] that they started dating recently is ridiculous.’’

“Go Maria!’’ one die-hard Kennedy-watcher told me. “She knows how to fight fire with fire.’’

A rep for Shriver told me “No comment’’ about Shriver’s relationship with Dowd, and two Schwarzenegger lawyers did not get back to me. Dowd sent a direct-message tweet to Palmeri, writing, “There was no affair. We were good friends.’’

Shriver, who is separated from Schwarzenegger but not yet divorced, is the granddaughter of the late family patriarch Joe Kennedy. She’s the daughter of the late Eunice Kennedy Shriver and counted as uncles both slain President John F. Kennedy and slain Sen. Robert F. “Bobby’’ Kennedy, as well as the late Sen. Edward “Ted’’ Kennedy.

Some women who marry into the Kennedys’ staunchly Democratic clan have had a hard time. The late Jacqueline Kennedy Onassis was stoic in the face of reports of her husband JFK’s paramours, and current family stalwart Ethel Kennedy turned a blind eye to tales of philandering by her husband, RFK. But Joan Bennett Kennedy, Ted’s first wife, in 1969 endured his drive off a bridge into the water off Chappaquiddick Island in Massachusetts with young staffer Mary Jo Kopechne, who died as Ted swam away. He pleaded guilty to leaving the scene of an accident causing injury and served not a minute in jail. Joan suffered from years of alcoholism, before divorcing Ted in 1982.

Mary Richardson Kennedy was the second wife and mother of four children of RFK Jr., who goes by the name Bobby, as did his father. She told a friend that she found 43 women’s names listed on his cellphone marked with the letter “G’’ — which she believed stood for “goomah,’’ the Italian slang word for mistress, The Post reported. The couple were in the midst of a divorce when, after years of suffering from depression and battling alcoholism, Mary Richardson Kennedy died in 2012 at age 52, hanging herself in the barn of the Westchester home she had shared with Bobby.

Kennedy women seem to be made of stronger stuff. RFK’s daughter Kerry Kennedy, 54, who works as the globe-trotting president of the Robert F. Kennedy Center for Justice & Human Rights, allegedly has a wandering eye.

In 2003, Kerry’s marriage to Andrew Cuomo, now 56 and the Democratic governor of New York state, imploded amid revelations that the mother of his three daughters was having an extramarital affair with Bruce Colley, now 61, a then-married, polo-playing fast-food tycoon.

Cuomo’s lawyer threw gasoline on the fire, releasing a statement saying that his client, whom I’ve never heard accused of cheating, was “betrayed and saddened by his wife’s conduct.’’ The couple divorced in 2005 and Cuomo now lives with TV chef Sandra Lee, 43.

Sex is a potent weapon in any woman’s arsenal. Use it wisely.

Chelsea out & it’s boo-who?

Chelsea Clinton last appeared on “NBC Nightly News” on Friday, Aug. 1, when she did a boring interview with actor Jeff Bridges about some program that feeds kids during the summer.

Anchorman Brian Williams looked shocked, saying that he hadn’t seen the former first daughter in a while as Chel stroked her pregnant belly.

Clinton, 34, announced last week that she was leaving NBC, which, Politico.com reported, paid her $600,000 a year to do almost nothing, in order to spend more time working for the Bill, Hillary & Chelsea Clinton Foundation.

Don’t let the door hit you you-know-where on the way out.

Bieber crashes & burns

Justin Bieber rides an ATV in January on a Panamanian beach.Splash News

Train-wreck pop runt Justin Bieber, 20, was with his on-and-off gal pal, actress/singer Selena Gomez, 22, in Canada last week when his all-terrain vehicle collided with a minivan and he got into a physical fight with the van’s driver. His lawyer told E! News that the paparazzi were to blame for following the Biebs and forcing him into being charged with dangerous driving and assault!

Bieber agreed to donate $50,000 to a charity and take anger-management classes in exchange for pleading guilty to charges of careless driving and resisting arrest without violence, after he engaged in what cops described in January as an illegal street race in his rented Lamborghini in Miami Beach, and is serving two years’ probation after pleading no contest to a vandalism charge for throwing eggs at a neighbor’s California mansion.

Whose fault was that?

Farewell to the late, great Joan of snark

Joan Rivers’ last words to me were vintage Joan — sassy and funny. “I’m gonna stand in front of Madonna’s house and I’m gonna throw paint­balls at her windows and let’s see if she then comes out and has me arrested,’’ the comedienne told me in an answering-machine message, thrilled to be among the celebrities I applauded in my Aug. 4 column for supporting Israel.

Pop diva Madge only expressed sympathy for Palestinian kids.

Joan Rivers died Thursday at age 81 in a New York hospital, a week after she stopped breathing during a throat procedure she underwent in a clinic.

I am grateful to have known her.