"I'm supporting due process of law and a fair and unbiased and honest investigation," he said.

Becky Noble, Baker's former campaign manager, said," I'm here to support my friend who's a police officer, and to support law enforcement. The level and hatred and disrespect I've seen for law enforcement just in this last week is disgusting. It's truly disturbing."

A man who said he was an undercover police officer and could not give his name was one of the leaders. The rally was posted on the Support Darren Wilson Facebook page, which shows thousands of supporters.

Rally organizers sold navy T-shirts with a picture of a white police badge with Wilson's name. Others at the rally wore T-shirts bearing the emblems of other police departments. Cars drove by honking in support.

On the pro-Wilson side, a staff sergeant stationed at Scott Air Force Base said, "It seems right now that you're only hearing one side from the media. There are other sides to the story."

Across the street, Aminah Lewis, 36, of St. Louis said she was there to counter the pro-Wilson rally because "I strongly believe Michael Brown was killed unfairly and as a human being, we all should expect to be treated fairly and not like a dog."