The Push-Back on Charter Schools

Geoffrey Canada, Harlem Children’s Zone, Richard D. Kahlenberg, Century Foundation, Jeffrey Henig and Luis Huerta, Teachers College, Columbia, Michael Goldstein, Match Charter Public School:

Two recent New York Times articles have described opposition to the thriving charter school movement in Harlem. An influential state senator, Bill Perkins, whose district has nearly 20 charter schools, is trying to block their expansion. Some public schools in the neighborhood are also fighting back, marketing themselves to compete with the charters.
This is a New York battle, but charter schools — a cornerstone of the Obama administration’s education strategy — are facing resistance across the country, as they become more popular and as traditional public schools compete for money. The education scholar Diane Ravitch, once a booster of the movement, is now an outspoken critic.
What is causing the push-back on charter schools, beyond the local issues involved ? Critics say they are skimming off the best students, leaving the regular schools to deal with the rest? Is that a fair point?