Michael will need the support today of 50 per cent plus one of voting members to avoid a leadership convention before the next provincial election expected sometime in the next 18 months.
The party had debated requiring two-thirds support for leadership reviews, but instead passed the lower threshold.
The party moved up its convention scheduled for next October after the very public crisis over Michael's ability to recruit new candidates.
The NDP had won historic gains in the 2011 provincial election and was riding high in public opinion polls before the damaging episode.
Two of five members quit the third-party caucus and now sit as Opposition Liberals in the Progressive Conservative-led government.