The Tax Policy Center has done an analysis of the tax proposals of Senators McCain and Obama. A lot of it is way too complicated for any of us to understand — and maybe for Senators McCain and Obama to understand, too — but here's the bottom line…
Although both candidates have at times stressed fiscal responsibility, their specific non-health tax proposals would reduce tax revenues by $3.7 trillion (McCain) and $2.7 trillion (Obama) over the next 10 years, or approximately 10 and 7 percent of the revenues scheduled for collection under current law, respectively. Furthermore, as in the case of President Bush's tax cuts, the true cost of McCain's policies may be masked by phase-ins and sunsets (scheduled expiration dates) that reduce the estimated revenue costs. If his policies were fully phased in and permanent, the ten-year cost would rise to $4.1 trillion, or about 11 percent of total revenues.
And here's the next-to-the-bottom-line…
The two candidates' plans would have sharply different distributional effects. Senator McCain's tax cuts would primarily benefit those with very high incomes, almost all of whom would receive large tax cuts that would, on average, raise their after-tax incomes by more than twice the average for all households. Many fewer households at the bottom of the income distribution would get tax cuts and those whose taxes fall would, on average, see their after-tax income rise much less. In marked contrast, Senator Obama offers much larger tax breaks to low- and middle-income taxpayers and would increase taxes on high-income taxpayers. The largest tax cuts, as a share of income, would go to those at the bottom of the income distribution, while taxpayers with the highest income would see their taxes rise.
There's a lot more to be read here, including a PDF of the entire report…but those are the money quotes. Anyone here surprised? The Tax Policy Center is somewhat partisan but I usually don't see many who disagree strongly with their projections on stuff like this. If you see another analysis that seems to, let me know.