Romney on taxes

Here are the key planks of Romney's tax plan:

- Bush-era income tax cuts and capital gains tax cuts become permanent.

- All income tax rates are cut by an additional 20 percent.

- The Alternative Minimum Tax and the estate tax are repealed.

Unless Romney gives a lot more specifics right now, the problem here is arithmetic: Factcheck.org notes that the idea that his plan can somehow "slash individual income tax rates without losing federal revenue or favoring the wealthy remains at best unproven, and in our judgment, based on available evidence, impossible."

Read more:

Romney offers new ideas on taxes and immigration (AP)

Conservatives challenge Romney's tax plan