Proving the issue is not dead yet, Sen. Mark Kirk is out with a new ad featuring two Illinois Dept. of Veterans Affairs employees at the center of a wrongful termination lawsuit against Rep. Tammy Duckworth.

The ad features the two women who allege that Duckworth, then the director of the state VA, told them to “keep your mouth shut” or be fired if they tried to report mistreatment of veterans at a facility in downstate Anna.

It proclaims, “Duckworth is a war hero. But she’s been a terrible public servant.”

The Duckworth campaign dismissed the suit as a “frivolous workplace case” in June.

But Kirk’s camp is keeping the issue alive, and perhaps for good reason politically. It allows them to tie Duckworth to convicted former Gov. Rod Blagojevich, under whom she served as director, while simultaneously going after one of her supposed strengths: veteran’s issues.

Kirk knows Duckworth has a built-in advantage given Illinois’ blue state status in presidential election years, especially with Donald Trump at the top of the ballot. However, the incumbent is not out of it just yet.

Kirk rescinded his endorsement of Trump earlier this year and said he would not vote for him. He has even run anti-Trump ads that played up his moderate credentials. Plus, Kirk has a track record of surviving against national headwinds.

As the congressman from Illinois’ 10th district, Kirk routinely represented the most Democratic House district held by a Republican. The same year President Obama won the district with 60 percent of the vote, Kirk was reelection with 51 percent.

He will need that ticket-splitting ability to translate statewide in order to win. And it’s not impossible. Though polling has been scant in this race, internal campaign polling in the last month has shown Duckworth ahead, but only in the mid-single digits.

The ad will run in the Chicago media market.