FERGUSON, Mo. – Phil Gassoway has spent the last 100-or-so days advocating justice for Michael Brown Jr., the black teen shot and killed by a white police officer here in August.

Gassoway has ducked and dodged rubber bullets and tear gas fired by police and braved extreme temperature and emotion. But these days, as a grand jury is poised to decide whether to indict Darren Wilson, the officer who killed Brown, Gassoway is hitting the streets and rallying for an unlikely player: Ferguson Police Chief Thomas Jackson.

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For weeks now, Gassoway, 35, has gone door-to-door with a clipboard and petition asking Ferguson residents to keep Jackson from being fired or replaced. Gassoway insists the issues in Ferguson go beyond the chief and that Jackson deserves more time to right the ship.

But Gassoway added there’s an even bigger reason to keep Jackson in office.

For the better part of a month, local, state and federal officials have been involved in meetings to try to develop a plan to force Jackson from his position. There’s even discussion of dissolving the Ferguson Police Department and handing over control of law enforcement in the city to St. Louis County Police.

The talks have reportedly included Democratic Sen. Claire McCaskill and have gone as high as the Obama administration. The Justice Department is conducting a civil rights investigation into Brown’s killing, and Attorney General Eric Holder has called for “wholesale change” in the Ferguson Police Department.

Gassoway told msnbc he had launched his mission to save Jackson after hearing McCaskill on a local radio show saying she thought the chief should step down. “I think it would be a good thing if we had change of leadership at the Ferguson Police Department, just because I think it’s important we start with a clean slate,” McCaskill told the station.

Gassoway said Jackson’s fate shouldn’t be decided by politicians.

“The people of Ferguson should be making the decisions about who our chief of police should be, not some government officials.”

Within about an hour, Gassoway had knocked on about seven or eight doors. All but about two signed his petition. The signees were a mix of young and old, black and white. To date Gassoway said he has collected about 1,500 signatures, with a goal of garnering 5,000.

Many were at first skeptical. But Gassoway has mastered his pitch. It’s about justice, he explains, and about Ferguson residents seizing their own power and exercising the agency to choose who their leaders are. He’s also gotten some of his fellow protesters to agree that there are larger problems in the community beyond a single police official.

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“They see that trying to throw all the blame on the chief of police and get the attention off of Darren Wilson off the prize and we want Darren Wilson actually prosecuted in jail,” Gassoway said. “They think if they give us the chief of police, it’ll quiet us down some. It’s not enough.”

Valerie Williams, one of the African-American residents who signed Gassoway’s petition, said she agreed that Jackson doesn’t deserve all the blame.

“That chief ain’t been here that long, so I’m not going to just criticize him,” Williams said.

Earlier that morning, Gassoway had arrived on South Florissant Road across the street from the Ferguson police station. He had organized a rally in support of Jackson in the same place that for months had been a hotbed of activity for protesters. “I used to sleep in a tent in front of the police department,” Gassoway said.

Ferguson Mayor James Knowles III had given Gassoway a verbal commitment he would show up. And Chief Jackson told msnbc the day earlier that he had heard about the rally and was humbled by it.

But as the 11 a.m. start time drew near, only a handful of people gathered on a corner across from the station. Of the dozen or so there, half appeared to be members of the media.

By 11:30 or so, with no mayor and no mass of supporters, Gassoway cancelled the event. He trudged into Cathy’s restaurant, a popular black-owned restaurant just up the block from the station. He was dejected.

“Here we are to support the administration and the mayor tells us that he has something else more important to attend to and that he’ll call us later. What is that?” Gassoway said.

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Amid all the political machinations and ongoing protests, the big decision by the grand jury to indict or not indict Officer Wilson is looming.

Local gun shops report that sales have gone through the roof, to prepare for possible violence if the grand jury does not indict the officer. Protesters have set up safe spaces to offer people refuge and medical care if they end up needing either. Gov. Jay Nixon on Monday afternoon signed an executive order to declare a state of emergency and mobilize the National Guard ahead of the grand jury’s announcement, which is expected any day.

Police and witnesses say Brown and Wilson engaged in a physical struggle through the window of the officer’s SUV shortly before the teen’s death on Aug. 9. Law enforcement officials say Brown attempted to take Wilson’s gun when the police officer fired the first shot. A half-dozen eyewitnesses have said they saw Brown flee the vehicle as Wilson open fire with the fatal shots as the teen stopped, turned and raised his arms in surrender.

But a government official who spoke on the condition of anonymity told NBC News’ Pete Williams Wilson had said he feared for his safety when the teen turned and charged back toward him after running from the vehicle.