The riding was held by Libby Davies, who has been the Member of Parliament in Vancouver East since 1997. Davies announced in December she will not run again.
"We are going to keep Vancouver East orange!," said Kwan as she thanked her supporters after results were announced at the Vancouver Technical School auditorium on East Broadwa shortly after 5 p.m. PT Sunday.
Kwan is a former Vancouver City councillor, who has represented Mount Pleasant in the B.C. legislature since 1996.
She was challenged for the nomination by Elmore, who was first elected to the B.C. Legislature in 2009.
With an election expected no later than Oct 19, Kwan is expected to play a key role on federal NDP leader Thomas Mulcair's team.