Democratic presidential candidate, Sen. Barack Obama, D-Ill, watches as he is introduced at a town hall-style meeting in Powder Springs, Ga., Tuesday, July 8, 2008. (AP Photo/Jae C. Hong)

Since his first primary victory in the snows of Iowa, Barack Obama has shown how to fill a stadium and fire up supporters with a promise of change.

In the last month — as his campaign turns to the general election — Obama has provoked his progressive political base with what many perceive as a shift to the center. On handguns, the death penalty, faith-based initiatives, and more, Obama sounds centrist.

He promised not to vote for a FISA wiretapping bill that shielded phone companies. Yesterday he did.

Jesse Jackson is up in arms. Others, too.

This hour, On Point: Obama takes heat from the left.

-Tom Ashbrook

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Guests:

Richard Wolffe, senior White House correspondent for Newsweek magazine.

Glenn Greenwald, contributing writer for Salon.com. His most recent book is “Great American Hypocrites: Toppling the Big Myths of Republican Politics.”

Katrina vanden Heuvel, editor and publisher of The Nation magazine and co-editor of “Taking Back America — And Taking Down The Radical Right.”

Fred Chamberlain, financial secretary of the Boilermakers Union in Croydon, Pennsylvania, and a supporter of Barack Obama.