Subsequent commercials with Mr. Aykroyd portray him in similar predicaments where his ignorance of global business also hurts him.

Mr. Dinkins is the first black candidate considered to have a strong chance of becoming the nominee of a major party, and ad professionals said his commercials effectively portrayed him as being thoughtful.

Although state television has stopped cigarette advertising, commercials on radio and in movie theaters portray smoking as a glamorous, cosmopolitan and - the ultimate cachet - American thing to do.

More than half the commercials portrayed older people engaged in physical or social activities like running and swimming, the study reported; none showed anyone in a hospital or using a wheelchair or walker.

So far Mr. Ravitch's commercials have portrayed him as a crusading builder of low-income housing and the financial wizard who improved the subway system.

But political commercials are increasingly portraying candidates as authentic people who tell the truth.

For several years, commercials for South African Breweries have portrayed blacks and whites working, playing and drinking together in the kind of integrated world that apartheid proscribed.

These more recent commercials have portrayed Pepsi Max consumers as unremarkable, average, and heavy men, explicitly identifying the target market.

In recent weeks, Mr. Labastida's commercials have portrayed those comments as treasonous.

Grey's commercials for Red Lobster, a unit of General Mills, have portrayed the restaurant chain as a place to go for sumptuously prepared seafood at a reasonable price.