Murali Pillai garnered 61.21 per cent of the votes, while Singapore Democratic Party's Chee Soon Juan got 38.79 per cent of votes.
The Elections Department said a total of 24,192 votes were cast, including 622 rejected votes, which made up 94.03 per cent of the 25,727 registered electors.
Chee, a vociferous opposition leader, had challenged the ruling party in the one-on-one contest.
President Tony Tan Keng Yam had issued the writ of election on April 20.
PAP, led by Prime Minister Lee Hsien Loong, has absolute majority in the house.