By Sadie Gurman, Pittsburgh Post-Gazette

In-your-face filmmaker Michael Moore came to Pittsburgh instead of Hollywood last night to show his latest rabble-rousing documentary, “Capitalism: A Love Story” to its first American audience, a spirited group of union workers energized by the AFL-CIO convention Downtown.

A last-minute change of plans and an invitation from the convention’s organizers brought Mr. Moore to the city, where he emboldened a crowd with stories of union struggles and victories, then led what he called a “march in support of single-payer health care” down Penn Avenue.

The crowd of 1,400, by organizers’ estimates, then filed into the Byham Theater, where Mr. Moore’s populist film elicited more hoots and cheers.

Critics have said “Capitalism” stands to be the Oscar-winner’s most controversial documentary yet; it not only denounces capitalism as a flawed economic system but also as one that is morally evil.

The Pittsburgh audience groaned when images of Ronald Reagan and corporate leaders flashed on the screen and cooed during the documentary’s darker moments, like when a tearful woman talks about losing to foreclosure the home she helped design and build on her family’s farm.

Speaking at the David L. Lawrence Convention Center before the premiere, Mr. Moore touched on a range of issues and lamented an economic system that, he said, puts the interests of a rich and powerful few above just about everyone else.

“The richest 1 percent have more financial wealth than the bottom 95 percent combined,” Mr. Moore shouted.

“Take it away from them!” the crowd yelled back.

“We have legalized greed,” Mr. Moore said. “Our laws say a company has a fiduciary responsibility to shareholders to maximize profits, and if they don’t do that, charges can be brought against them.”

In the health care insurance industry, Mr. Moore said, a profit is made by denying benefits and care.

Mr. Moore also encouraged the crowd to stand behind President Barack Obama in his fight to reform the nation’s health care system, saying he hoped “President Obama can be the FDR of the 21st Century.”

“I don’t see us on the nightly news, I don’t see us packing the town hall meetings,” he said. “I see Barack Obama on his own. Who’s got his back?”

“We do!” the crowd cheered.

Mr. Moore then led rallyers, who waved signs and chanted slogans — “hey, hey, ho, ho, insurance companies have got to go,” — down Penn Avenue, as patio diners and police officers looked on.

“There’s so many workers here struggling,” said Leslie Curtis, of the California Nurses Association, who yelled into a megaphone during the march. “The labor unions really feel this single-payer message.”

Mr. Moore’s trip came a week before world and economic leaders will gather here for the G-20 summit; he said he might return during the summit, too, perhaps for another showing.