Populist Reform of the Democratic Party

You could very easily do positive push polling, simply by asking questions about Elizabeth Warren and Bernie Sanders on various topics, having the listener 'rate' them on those topics, then tell them some positive and truthful info about Warren and Sanders and ask them if that makes their opinion of Warren or Sanders increase, decrease, or stay the same.

In reality, although it's a 'poll', you don't care what the responses are, the point is actually in making the listeners more familiar with the stances of and more favourable towards Warren and Sanders.

So for example, you ask the person how they would rate Sanders on his support of the poor and middle class. They answer, then you read them a quote like 'They talk about class warfare - the fact of the matter is there has been class warfare for the last thirty years. It's a handful of billionaires taking on the entire middle class and working class of this country. And the result is you now have in America the most unequal distribution of wealth and income of any major country on earth and the worst inequality in America since 1928. How could anybody defend the top 400 richest people in this country owning more wealth than the bottom half of America, 150 million people?'

(Ok, that quote was on the long side, but you get the idea.)

Then you ask them if knowing Sanders said that makes them more favourable or less favourable towards him.

There are PLENTY of quotes from Sanders and Warren both that could be used this way, and it gets their message out to some for the first time, to others as a reinforcement if they've heard it before.

And none of it is negative, and none of it is lies.