Presidential hopeful Tan Jee Say has the support of Ms Nicole Seah, in her "personal capacity".
In a video clip dated July 30, which Mr Tan posted yesterday on his Presidential Election website, Ms Seah said: "I just want to say that I want to endorse Tan Jee Say for president because I think he really has what it takes.
"We need a president who is intellectual, who is a brilliant thinker, and not only that - someone who has a heart for the people, and who can represent Singapore on the greater world stage. So please vote for Tan Jee Say."
Mr Tan, 57, an investment adviser and former high-ranking civil servant, also posted two other video clips on the website (www.tanjeesay.com).
In one clip, at Bugis Junction mall, National Solidarity Party's Ms Seah said she was helping Mr Tan to do a spot of shopping as "he's in dire need of new clothes".
With them was private school teacher Michelle Lee of the Singapore Democratic Party.
Mr Tan has resigned from the SDP to run for presidency.
The clips are no surprise given that all four Tans - the three others are Tan Kin Lian, Dr Tony Tan and Dr Tan Cheng Bock - have embraced social media in the run-up to the Presidential Election, which must be called by the end of the month.