Unfortunately, as a political football supply side economics has come to mean simply 'tax cuts' and the idea that some tax cuts can spur further economic growth which will still produce similar or higher tax revenues than without the tax
cuts.

Which is an idea with some (but limited) merit but which over time has come to be the idea that cutting any tax by any size will have the same impact. This is nonsense.

So what does any of this have to do with Jesus?

Supply-side economics are generally associated with conservative politics, many of whom subscribe to the theory but only follow through on portions of the tenets. (Such as the type of tax cutting Alex referred to above). Critics and more cynical people like myself think that it's just a ploy to keep money in the rich person's pockets while letting the poor fend for themselves. Jesus did not hold the rich in high regard, as such statements as "It is easier for a camel to pass through the eye of a needle than it is for a rich man to reach heaven" and "the meek shall inherit the earth" bear out. He had a real problem with the Pharisees, a well-to-do and influential religious sect in the Jewish community, who were not very good about taking care of the poor, and arrogantly thought that their largess was bestowed upon them (from God) because they were righteous. Of course, this is a really simplistic take on a very complicated history and economic theory, but Franken was pointing out that Jesus probably wasn't a supply-side sort of guy.