The Ohio Democratic senator Sherrod Brown endorsed a key voice in the American public square – Cookie Monster – in a complaint about shrinkflation.

“Me hate shrinkflation!” the Sesame Street character posted on social media on Monday, referring to an economic phenomenon Merriam-Webster defines as “the practice of reducing a product’s amount or volume per unit while continuing to offer it at the same price”.

“Me cookies are getting smaller,” Cookie Monster added, appending a frowning face emoji.

Brown, a leading progressive in the US Senate facing a tough fight for re-election, said: “Me too, Cookie Monster. Big corporations shrink the size of their products without shrinking their prices, all to pay for CEO bonuses. People in my state of Ohio are fed up – they should get all the cookie they pay for.”

Cookie Monster’s tweet was not the first from a Sesame Street character to make news in recent weeks. Last month, Elmo, the particularly toddler-friendly red furry muppet, prompted an outpouring of existential dread when he simply asked followers: “How is everybody doing?”

Nor was Brown the first prominent Democrat to seize on shrinkflation as a campaign issue. Last month, Joe Biden used a video released on Super Bowl Sunday to say the American public was “tired of being played for suckers” by makers of popular snacks.

“Some companies are trying to pull a fast one by shrinking the products little by little and hoping you won’t notice,” the president said.

“Sports drinks bottles are smaller, a bag of chips has fewer chips, but they’re still charging just as much. As an ice-cream lover, what makes me the most angry is that ice-cream cartons have actually shrunk in size.”

On Monday, Biden – or at least the White House social media team – took time to join Brown in backing Cookie Monster’s complaint.

“C is for consumers getting ripped off,” a retweet of Cookie Monster’s original message said. “President Biden is calling on companies to put a stop to shrinkflation.”

Biden’s love for ice cream is as well known as Cookie Monster’s love for cookies, though both president and puppet advocate for children to eat healthy foods too.

Among some observers, meanwhile, Brown’s agreement with Cookie Monster about the evils of shrinkflation prompted thoughts of another similarity between the senator and the Sesame Street star.

Both are known and celebrated for distinctive, gravelly voices.

The historian Kevin M Kruse once said Brown sounded “like Tom Waits smoked a carton of Pall Malls and gargled hot asphalt”.

Cookie Monster – originally provided by the celebrated puppeteer Frank Oz, now performed by David Rudman – has also been widely compared to Waits.