The Together for Yes campaign has raised half a million euro in four days.
The group set up a crowdfunding page on Tuesday with an original target of 50 thousand euro.
On the day the campaign launched, the level of donations worked out at around 19 thousand euro an hour.
There were over 12 thousand individual donations which averaged out at around 38 euro per person.
The funds will be used for a national poster and leaflet drop campaign.