Amid tight security, Mr Wilders made a rare public appearence in his Freedom Party's stronghod of Spijkenisse, where he shook hands with supporters and posed for photographs.
Opponents of the far-right candidate – who has promised to shut down mosques and ban the Koran – stood holding placards bearing pro-immigrant slogans.
Mr Wilders told the crowd: "There is a lot of Moroccan scum in Holland who make the streets unsafe.
"If you want to regain your country, make the Netherlands for the people of the Netherlands again, then you can only vote for one party."
It is not the first time Wilders has targetted Moroccans. He was convicted in December of inciting racial discrimination for comments made in a 2014 post-election speech.
The populist has been dubbed the "Dutch Trump" – a right-wing firebrand whose inflammatory anti-Islamic rhetoric echoes that of the new US President.
This week he promised to 'de-Islamisise' the Netherlands, and said he would change the country's constitution if necessary.
Mr Wilders tsaid: “A constitution is not something that is (set) in stone and can never be changed.
“It is alive as a society is alive and we are now being threatened by mass immigration and Islamisisation and what I see as the toxic combination of mass immigration from Islamic countries."
He also described Islamic faith as "possibly more dangerous" than Nazism – comments which were heavily condemned by Spior, an Islamic organisation representing 70 mosques and Islamic groups in the Netherlands.
Geert Wilders launches his election campaign
Mr Wilders seldom goes out in public and when he does is surrounded by a huge security entourage, due to frequent death threats and attempts on his life.
He is hoping the wave of populism across Europe and the US will carry him to victory on March 15, paving the way for more election wins for far-right candidates like Marine Le Pen in France.
His Freedom Party currently leads polls with 17 per cent, although the pro-business liberals of Prime Minister Mark Rutte have closed the gap on Mr Wilders to a percentage point by matching some of his anti-immigration rhetoric and getting an electoral boost from a surging economy.
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Geert Wilders called Moroccans 'scum' during his campaign launch
Wilders holds a fake banknote with his face on it as he meets supporters
However all mainstream parties, most recently and notably Rutte's party, have ruled out working with Mr Wilders because of his anti-Islam stance.
His one hope may lie with Thierry Baudet, leader of anti-establishment minority party Forum for Democracy – who has cast himelf in the role of kingmaker in the upcoming elections.
Baudet predicts his party will enough parliamentary seats to form a coalition with the PFreedom Party – and has publicaly stated his willingnes to work with Mr Wilders.
The next Dutch parliament is also unlikely to support policies such as quitting the European Union.
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