Former President Clinton is taking to the airwaves to try and save his in-law, former Rep. Marjorie Margolies (D-Pa.), an in-law of the Clintons who is running for her old seat.

"I'm not coming here saying vote for her because 20 years ago she saved the economy," Clinton says in the ad, referring to Margolies's support of his budget in 1993. She was the deciding vote for it, and the vote likely cost her reelection the year after. 

Margolies's son, Marc, is married to Chelsea Clinton, and the two are expecting a baby later this year. 

"She'll take initiative. She'll do things and stand up when she needs to stand up and cooperate when we need cooperation," the former president continues. 

The ad could help boost Margolies, whose campaign has been struggling some despite her early front-runner status. She is locked in a hard-fought primary next Tuesday with Pennsylvania state Rep. Brendan Boyle (D), state Sen. Daylin Leach (D) and physician Val Arkoosh (D) heading into next Tuesday's primary.

She's struggled with fundraising and has faced questions about whether she's broken campaign finance law by using funds earmarked for the general election in the primary. Outside groups, including EMILY's List and Planned Parenthood, have been pounding Boyle for his record on abortion, a sign he's emerged as her biggest threat.

The Clintons have already been helping Margolies in her crowded primary in a big way — the ad's footage is taken from a recent fundraiser Bill did for her, and former Secretary of State Hillary Clinton will fundraise for her in Philadelphia in the coming days.

—This post was updated at 10:48 a.m.