How well do minimum wage increases target poverty?

David Henderson writes:

Economists Joseph J. Sabia and Richard V. Burkhauser examined the effects of state minimum wage increases between 2003 and 2007 and reported that they found no evidence the increases lowered state poverty rates.

Further, they calculated the effects of a proposed increase in the federal minimum wage to $9.50 on workers then earning $5.70 (or 15 cents less than the minimum in March 2008) to $9.49. They found that if the federal minimum wage were increased to $9.50 per hour:

. Only 11.3 percent of workers who would gain from the increase live in households officially defined as poor.
. A whopping 63.2 percent of workers who would gain were second or even third earners living in households with incomes equal to twice the poverty line or more.
. Some 42.3 percent of workers who would gain were second or even third earners who live in households that have incomes equal to three times the poverty line or more.

There is more from David here.