First look: Biden's tough "Knock on the Door" ad

Joe Biden, believing President Trump is suddenly vulnerable with military voters, goes up today with an ad called "Knock On The Door," featuring retired Air force Brigadier General John Douglass, a former casualty notification officer.

• Douglass — who grew up in Florida, and now splits time between Virginia and Florida — used to deliver the dreaded "knock on the door" to military families, letting them know their loved one had made the ultimate sacrifice.
• Douglass, referring to accusations — which Trump disputes — in a widely covered article by The Atlantic, says in the ad: "These military families suffer, and those spouses are not suckers. And those children are not losers."

What I'm hearing: The Biden campaign argues that reports of Trump privately disparaging service members have broken through with everyday people who don't follow, or don't care about, other Trump scandals.

• A poll of registered voters in military households by Politico/Morning Consult found an astonishing 73% had heard the reports.

The ad will air on TV and digital platforms in Arizona, Florida, Pennsylvania, North Carolina, and Wisconsin — targeting media markets and areas with a high number of military households and veterans.

• Biden ads remain active in a total of 10 states — the ones above plus Michigan, Nevada, Ohio, Nebraska, and Minnesota. 

The other side: Trump has denied the accusations by The Atlantic, as have many current and former aides. A key figure in the article — retired Marine general John Kelly, a former Trump chief of staff — hasn't spoken publicly about it.

• Trump campaign communications director Tim Murtaugh told me: "Servicemen and women know that President Trump restored the military to its rightful strength and fixed the scandalous problems at VA hospitals."