The poll funded by Infotrak shows the number of undecided voters has fallen by two percentage points.
The Ipsos survey was conducted between July 2 and July 12 while Infotrak polled from July 16 to July 22.
Kenyan opposition leader and Nasa presidential candidate Raila Odinga has gained support over the ruling President Uhuru Kenyatta in the latest survey by pollster Infotrak.
In the survey released on Sunday, Mr Odinga’s approval rating has grown by four percentage points since the end of June — from 43 per cent to 47 per cent.
Mr Kenyatta’s has dropped by two points — from 48 per cent to 46 per cent.
It is the first time Mr Odinga is overtaking Mr Kenyatta in Infotrak surveys, although a Nasa-funded poll by Zogby recently placed him at 47.42 per cent against Mr Kenyatta’s 46.63 per cent.
It is also the first time Mr Kenyatta’s approval rating is falling — it stood at 46 per cent in February and 48 per cent in June.
Leadership
Regarding the steep rise in Mr Odinga's popularity, Ms Angela Ambitho, the managing director of Infotrak, said: "More people have decided. Nasa had more undecideds in their strongholds than Jubilee did.
"Maybe it has dawned on the 50 per cent who think the country is headed in the wrong direction that those to blame should go home..."
The poll funded by Infotrak shows the number of undecided voters has fallen by two percentage points — from eight per cent in June to six per cent.
"It is really a dead heat right now — a tie statistically. And what will decide who wins in the first round is the number of undecided," Ms Ambitho said as she released the poll in Nairobi.
"Can this election be won in the first round? Yes. From the numbers, it is the battle of the undecided that will carry the day."
Tough contest
The Infotrak poll came hours after an Ipsos survey showed the race for State House remains tight, with Mr Kenyatta and Mr Odinga locked in a fierce battle.
According to Ipsos, the approval rating of Mr Kenyatta has dropped by a point while that of Mr Odinga has risen by a similar margin, the poll released on Sunday morning shows.
The poll also shows that Mr Kenyatta has the backing of 47 per cent of Kenyans, from 48 at the end of June, while Mr Odinga is at 43 per cent from 42 per cent.
Some five per cent of Kenyans are yet to make up their minds, the survey with a 2.09 per cent error margin shows.
However, it should be noted that the two surveys were carried out at different times.
Interviews
The Ipsos survey was conducted between July 2 and July 12 while Infotrak polled from July 16 to July 22.
A sample of 2,000 respondents drawn from 31 counties and 100 constituencies took part in the Infotrak survey that had a 2.19 per cent margin of error.
Data, according to Ms Ambitho, was collected through household computer-assisted personal interviews.