A new opinion poll by Radio Africa Group shows Kahiga, who is the incumbent, commands 48.1 percent of the votes.
Senator Ephraim Maina, who is vying on a Jubilee ticket is second with 16.5 per cent while Thuo Mathenge of The New Democrats is third with 10.4 percent.
Peter Munyiri of Chama Cha Kazi is fourth with 4.1 percent while Gachara Kamanga, who is independent, has 2.3 percent.
The other aspirants are controlling 1.4 percent, 13.9 percent said they were undecided while 3.2 percent said they will not vote.
The polls were conducted between May 4 and 8 using SMS-based interviews.
For the Nyeri senatorial race, UDA aspirant Wahome Wamatinga is leading with 38.3 percent.
He is followed by Priscilla Nyokabi of Jubilee with 23.4 percent while Kabando Wa Kabando of Narc Kenya while other aspirants have 0.6 per cent.
15.3 per cent of voters are undecided while 3.9 per cent said they will not vote.
For the Woman Representative seat, UDA aspirant Rahab Mukami is leading with 48.4 per cent followed by Njeri Njori of Jubilee with 18.5 per cent.
Other aspirants have 7.0 per cent, 18.8 per cent said are undecided while 7.3 per cent said they will not vote.
In Nyeri, UDA is the most popular party with 42.7 percent, followed by Kenya Kwanza 20.4 per cent, Azimio la Umaja is third with 17.2 per cent while Jubilee is fourth with 6.6 per cent.
