Madam Sherifa Tijani Sekyere Saturday polled 289 votes to defeat Mr Maxwell Blagogee, the Deputy Oti Regional Minister, and two others at the Nkwanta South New Patriotic Party (NPP) parliamentary primaries.
Mr Blagogee polled 262 votes but not enough to see him through.
Mr Daniel Kunyo had 53 votes and Joseph Durunya had 22.
There were eight rejected ballots out of a total of 634 votes cast.
Madam Sekyere promised to work with all, especially her contenders, to win the seat for the NPP in the 2020 general election.
Mr Blagogee, after the polls, declined to talk to the media.
The polls were supervised by officials from the Electoral Commission.