"Muppet" in American English

I see an event is being organised in Washington, DC, called the Million Muppet March. In British English, at least, muppet has no very positive connotations:-

muppet (ˈmʌpɪt) — n slang a stupid person

Is that also the case in American slang?

Solution 1:

In American English, 'muppet', capitalized or not, has no meaning other than being characterized by the Jim Henson branded characters. The idea of it being a 'stupid person' is unknown. Some of the Muppet characters are slow, others are bright, others have other personality traits.

To call someone in the US a muppet would only make one wonder, 'Which one? Miss Piggy? Fozzy? Beaker?'

Solution 2:

They are genuinely going to march with Muppets (capitalised and trademarked) to protest the cutting of funding for PBS (who hosts Sesame Street)

WSBT

A grassroots protest to save PBS funding, dubbed the Million Muppet March, is scheduled for Saturday, Nov. 3 -- three days before the presidential election -- at the National Mall.
Mitt Romney's threats during the first presidential debate to cut federal subsidies for PBS galvanized support for the "Sesame Street" network -- including Michael Bellavia and Chris Mecham.

Muppet (n.)

Trademark (U.S.) Sept. 26, 1972, claiming use from 1971, but in print from Sept. 1970. Name coined by creator Jim Henson (1936-1990), who said, despite the resemblance to marionette and puppet (they have qualities of both), it has no etymology; he just liked the sound.

As for the question about the slang, I would think calling someone a muppet will be negative in any language, denoting a person with someone else's hand up inside making them do their bidding

muppet - Urban Dictionary:

A person who is ignorant and generally has no idea about anything.

Solution 3:

As a dual citizen of both countries I can say beyond a doubt there is no American equivalent of the British slang word muppet. Same goes for plonker, wally, jesse and many many more. The British are very creative.