WATCH: The Lincoln Project goes after Susan Collins with hard-hitting attack on her credibility
Republican Sen. Susan Collins of Maine (screengrab)

The Lincoln Project is once again going after Sen. Susan Collins of Maine.

The new ad is actually a Susan Collins re-election ad defending her integrity.

But the Lincoln Project modified the ad with a Seinfeld-like laugh track.

Collins is being challenged by Sara Gideon, the Speaker of the Maine House of Representatives in the November election.

On Wednesday, the Lincoln Project hit Collins with a different ad, titled, "Trump Stooge."