'Akilisi Pohiva's tenure was cut short in August when the King dissolved parliament amid allegations the government had been acting unconstitutionally.
Mr Pohiva had been criticised for his leadership style but survived a motion of no-confidence.
Kalafi Moala, who runs the Taimi Media Network, said Mr Pohiva's constituency had the most candidates this election.
He said Mr Pohiva may still have enough support to return to parliament but not to the prime ministership.
"When you look at it technically, the vote is going to be spilt among 10 people. It is very, very possible, probable in fact, that Pohiva can win this district with a minority. I think if he wins 30 percent of the vote, he will take this district.