While the top personal income tax rate in California is now 10.55%, even the average income earner pays a marginal income tax rate on the next dollar earned of 9.3%.

FORBES: The Anachronism Of State Income Taxes

Note that closing loopholes may well raise the average corporate rate, on which Democrats and liberals have focused, but it is the marginal tax rate that drives the economy, as discussed above.

FORBES: The GOP Jobs Plan Vs. Obama's

Add in state taxes of 5 percent (on average in many states), and the top marginal tax rate is 50 percent.

FORBES: Raise Taxes To Kill A Recovery And Nail The Coffin Shut

The average U.S. top combined state-federal marginal tax rate would hit about 52%.

WSJ: A Reckless Congress: Health-care bill to impose new taxes, welfare state

The Lib Dems, who want to lower the basic rate of income tax, said the plans would only result in a marginal saving for people on average incomes.

BBC: Cameron makes savings tax pledge