Donations from the public have so far ranged from $2 to $1,000, which were transferred to the blogger's bank accounts and PayPal.
Ngerng is hoping to raise up to $70,000 in this first tranche of donations from the public to build up his war chest to go to trial, which is expected to last for a year.
PM Lee's lawyer first issued a letter of demand to Ngerng for an apology and for the removal of an article alleging misuse of CPF funds on May 18, 2014.
This was followed by an exchange of a series of lawyers' letters between both sides.
After PM Lee rejected Ngerng's offer of $5,000 in damages, a defamation lawsuit against the blogger commenced.
A writ of summons was filed with the Supreme Court on May 29, where the value of claims for civil cases generally exceeds $250,000.
However, the $70,000 sum that Ngerng hopes to raise from the public is intended to only cover the cost for his lawyer M Ravi.
It is not known for how long Ngerng's appeal for donations will last as it will also depend on how much aggravated damages is eventually awarded, if and when the court does rule in favour of PM Lee.