The JustGiving page surpassed its £2,000 target within hours of its creation.
Mr Brolly was a popular figure in Derry and was known affectionately as ‘Scotch Jimmy’.
He passed in Altnagelvin Hospital on Monday after a short illness.
Said the Foyle MLA: “The affection that this city had for Jimmy has been palpable since his passing.
“The outpouring of sadness and stories around social media are testament to the place he held in the hearts of people here.
“Many of us will have experienced the warmth of Jimmy’s personality as, despite his own difficulties, he always strived (and usually succeeded) to make other people smile.
“Jimmy has left no known family or estate and as such I appealed to the well-known Derry generosity for contributions so that Jimmy could be given a dignified send off.
“Within hours last night we were able to reach our set target of £2,000.
“I must thank everyone who donated for their kindness- we now have enough to cover funeral costs and for a modest memorial.
“Jimmy will be greatly missed, not least by the staff of Damian House.”
Jimmy’s Funeral will take place tomorrow, Thursday 14th November 10am at St Mary’s Creggan followed by burial in the city cemetery.
Adair & Neely Funeral Home, Foyle Road will be open on Wednesday evening from 7 pm – 9 pm for friends to pay their respects.