The retired Canadian Armed Forces colonel is set to make an announcement at a downtown Ottawa hotel.
Stogran is already registered as a candidate on the Elections Canada website.
NDP MPs Niki Ashton, Peter Julian, Guy Caron and Charlie Angus are also registered, along with Ibrahim Bruno El-Khoury, the founder of a Montreal consulting firm.
The NDP says Stogran and El-Khoury must submit nomination paperwork and a registration fee in order to be official candidates.
WATCH: NDP leadership debate focuses on Liberals’ marijuana promises
A court settlement also clears the way for the NDP to reconsider the bid of a Toronto man who took the party to court after it rejected his application late last year.
Brian Graff had argued that the party unfairly blocked his entry into the race with no reasons or explanation.
A statement Tuesday says key to the settlement was a commitment by the party to take another look a Graff’s application.
The race to replace Tom Mulcair at the helm of the NDP ends in October.