The ribbon and checkmark go by in a flash — less then two seconds in a 15-second digital ad — with Pennsylvania State Rep. Brian Sims smiling next to a picture of State Attorney General Josh Shapiro.

Three words in that frame — “endorsed Josh Shapiro” — provoked Shapiro to send Sims a “cease and desist” letter, demanding that the ad be pulled.

Shapiro, the only Democrat on the May 17 Democratic primary ballot for governor, in early January endorsed State Rep. Austin Davis of Allegheny County for lieutenant governor. The state Democratic party endorsed the Shapiro-Davis ticket in late January.

A lawyer for Shapiro’s camp wrote to Sims Friday that his ad “suggests” Shapiro endorsed him.

Shapiro’s campaign notes it is “unorthodox” for Shapiro to endorse in the lieutenant governor’s primary, making it “so valuable” to Davis, and accuses Sims of trying to “mislead viewers.”

Sims was on a shortlist of potential running mates for Shapiro last fall before Davis got the nod. The campaigns have thrown some sharp elbows as the primary nears.

Sims pushed back Monday with a letter from his own lawyer, pointing out that the ad only says Sims has endorsed Shapiro. Davis is free, Sims’ campaign said, to run his own ads.

That’s on the horizon. Davis has $1.2 million in broadcast and cable television booked for the closing weeks of the primary. His ads are — you guessed it — full of smiling Shapiro pictures and endorsement checkmarks.

Sims is at the financial disadvantage here. He had $317,000 in the bank as of March 28 while Davis had $625,000 and Shapiro had $16 million.

Kunal Atit, Davis’ campaign manager, called Sim’s ad “deceptive and unethical,” noting that seven Democratic state House and Senate caucus leaders issued a letter last month complaining that Sims puts “his own self-interests above that of the party.”