Hope Yen of the AP writes in today's Arizona Republic 12/15/2011 p. A1
"Squeezed by rising living costs, a record number of Americans, almost one in two, have fallen into poverty or are scraping by on earnings that classify them as low-income.
The latest census data depict a middle-class that is shrinking as unemployment stays high and the government's safety net frays..."
The low income threshold is $45,000 a year for a family of four.
The article states that approximately 97.3 million Americans are classified as low-income while 49.1 million are classified as falling beneath the poverty threshold.
In total, 146.4 million, or 48% of the population, are considered low-income and below.
The article doesn't state what percent of this group is made up of children under 18 but I'm sure it is high.