Producer Mark Ciardi on “Chappaquiddick” and the Kennedys

Film producer Mark Ciardi loves an underdog story, which explains entries in his IMDb registry such as “The Rookie,” “Secretariat” and “Million Dollar Arm.” (He’s also a former professional baseball player who played in college for the University of Maryland, which explains his affinity for sports tales.)

But most of all, he says, his favorite films are “true stories.” Which brought him to his latest project, “Chappaquiddick,” about the scandal that threatened to thwart the political career of Sen. Ted Kennedy, DMass.

In the summer of 1969, the young senator drove his car off a bridge, killing his passenger, Mary Jo Kopechne, who had been an aide on the presidential campaign of his brother, Robert Kennedy. The drama, which hits theaters next month, stars Jason Clarke of “Zero Dark Thirty” as Kennedy, actress Kate Mara as Kopechne, and Oscar winner Bruce Dern as patriarch Joe Kennedy.

A: About three years ago, I started an independent movie company. A friend called and said he had a script that was really good, so I read it and just fell in love with it. It read as a political thriller and an interesting part of American history.

Q : Was it hard to cast

When you’re portraying someone that iconic, you need someone who resembles the character, and Jason does. He used a little enhancement — the teeth, the hair, and he used a dialect coach. And then he looked really like him. You get a sense when you’re watching that this is Ted Kennedy — it’s not like you’re like, “Oh, it’s that actor playing Ted Kennedy.”

A: We didn’t get pushback when we were filming. We shot a couple days in Chappaquiddick and the north shore of Boston. Now, through the grapevine, I don’t think the family is particularly happy.

I think it was a fair portrayal. We did a screening in Martha’s Vineyard last week, and there were people who had known the Kennedys there. I think people were appreciative of how we handled it. Obviously, it’s not flattering; you can’t get around that.

A: So we started making the film in 2015, before Trump was a factor. And I think people will have their own takeaways, whether they are on the left side of the aisle or the right. But we really wanted to make this a nonpolitical film.