The last Democrat to get elected president on an openly liberal platform was Lyndon B. Johnson, nearly 40 years ago. Since then, both Jimmy Carter and Bill Clinton have won with a pretense of moderation. Walter Mondale lost in a landslide in 1984, when he tried to run as an openly liberal politician -- out of the closet, as it were.
The typical liberal politician is soft on criminals, weak on defense, and ready to tax the daylights out of those who produce, in order to dispense largesse to parasites, rich and poor alike. The public isn't buying it. Indeed, liberal politicians aren't trying to sell it very much.
Instead, they rely on promoting fears and resentments among the elderly, blacks, gays, and others. If they can convince senior citizens that conservatives are going to take away their Social Security or Medicare, they have got a lot of votes.
If they can promote paranoia and resentment among blacks by crying "racism" at every turn, they have the inside track. And if they can keep black voters' attention focused on symbolic issues like confederate flags -- instead of how their children are trapped in failing schools, for the greater glory of the teachers' unions -- then the Democrats can continue to get nine out of 10 black votes.
While fomenting fear and envy may gain votes, it isn't enough for talk radio, which is ultimately about ideas. Liberal talk show hosts don't have any goodies to hand out, the way liberal politicians do.
Al Franken is the perfect man to try. He has written a book titled "Rush Limbaugh is a Big Fat Idiot." Competition is the way to find out who is the idiot. I would offer to bet but I would just be taking your money.