All sorts of people benefit from capital gains tax cuts, not just the much despised "rich." The single biggest thing they could do to make the capital gains tax reasonable would be to index it to inflation. Here's an example:

Suppose you buy something today for $10,000. In 20 years, you find someone who'll pay you $20,000 for it. Cool, you made a $10,000 profit on your investment, right? Well, not really.

If the average inflation rate over that 20 year period were 3.5%, there would be zero dollars of profit in real dollar terms. Why should people have to pay taxes (under current law, $2,000) on something that increases in price solely in keeping with inflation?

Capital gains taxes are applied to all sorts of things. Do you have a traditional IRA or 401K that's invested in stock? If so, then you're going to get hit with capital gains when you go to sell your shares, even if the price only kept pace with inflation. Does that sound reasonable? Over half of all Americans are invested in the market so it isn't only the evil RICH that will benefit.