2001 year end, 10% of the population owned 71% of the wealth and the top 1% owned 38%. In 2003, the top 1% paid more than 34% of the nation's federal income tax; the 10% with the highest income paid nearly 66% of the total income tax; the top 25% paid 84% of the income taxes; and the upper 50% accounted for nearly 97% of US income tax revenue.
(Looks like the sad sacks of the lower 50% could pay more.)