An online petition is asking Mayor Rahm Emanuel to let Occupy Chicago protesters stay in Grant Park without being arrested.
Organizers of the local anti-Wall Street protest say the petition had collected nearly 10,000 signatures Friday.
Police arrested 175 protesters early Sunday after hundreds refused to take down tents and leave Grant Park when it closed at 11 p.m. the night before.
Organizers didn't seek a permit to be in the park after hours, saying they stayed because they need a home base for the growing movement.
The petition asks Emanuel to stop the arrests and respect protesters' right to assemble.
It also says, "Don't let this end like 1968," an apparent reference to the Democratic National Convention of that year when Chicago police violently clashed with about 10,000 protesters.