A spokesman for a group supporting the Michener Centre in Red Deer says more than 1,500 people have signed on.
Bill Lough with the Society of Parents and Friends of the Michener Centre says volunteers are collecting even more signatures by going door to door.
Law says it hasn't yet been decided when to present the government with the petition.
The province announced earlier this year that it plans to move 125 Michener residents to community group homes or seniors facilities.
A rally in Red Deer last week to protest the planned closure drew about 250 people.
Lough says the response has been nothing but positive.
"One of our petitioners reported back that ... no one refused to sign her petition and actually several asked for copies of it so they could distribute (it). This is an excellent vehicle for expressing the public's opinion."
Friends and family of Michener residents say the centre is the only home many of their loved ones have ever known. Michener supporters say there aren't adequate services in the community and people moved out of the centre won't do well.
Red Deer MLA Mary Anne Jablonski has said she understands why the decision is hard for people to accept, but she has given her assurances that residents will be moved with care and consideration.
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