Aside from UDM, Ruto's party has also tapped majority of independent candidates.
He has been on a poaching drive, even as in his victory speech he said he supported a strong opposition.
The first action of the president-elect has been to raid Azimio ranks for support to push his agenda in the two houses as well as the council of governors.
If confirmed as president, his government, with their support on his side, will have removed the threat of an Azimio majority and can railroad Ruto's agenda or plans such as passing crucial Bills, and vetting and approving nominees to the Cabinet, Principal Secretaries, ambassadors, and high commissioners.
But Ruto's gain is Azimio la Umoja's loss.
But even as its members pledge their allegiance to Ruto, UDM is still legally tied to Azimio. It is one of the 26 parties that signed an agreement to create Azimio la Umoja as a coalition political party.
Registrar of Political Parties Ann Nderitu said yesterday that there was no provision to limit political parties and members from associating but the parties are bound by the pre-election agreement they signed.
"They can associate however they want but they cannot be in two coalitions - they have to resign from one. So far, I have not received a request from any party that wants to leave a coalition," she said.
Azimio also took offence with what they labelled as attempts to retard the growth of multiparty democracy.
Makau Mutua, who was the spokesman of the Raila presidential campaign and head of his think tank, said that Ruto was disregarding the rule of law by wooing Azimio and independent MPs-elect and governors-elect to defect to his side .
He said that the move was to defeat the independence of the legislature.
"Mr Ruto preaches water but drinks wine. He ought to know democracy requires vibrant pluralism in which different political parties compete on issues. Attempts to cannibalise Azimio will not succeed," he said.
Mutua said that Azimio La Umoja-One Kenya - and its Deed of Agreement - set out the ground rules and conditions under which members can exit the coalition. There are clear guidelines.
"Mr Ruto should know that it is illegal for him, or others, to induce members to purport to leave Azimio. No member of Azimio has legally invoked the process of leaving the coalition. All the members who signed as original members are still members in good standing. So, any purported defections are a legal nullity," he said.
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Azimio now has 155 votes in the National Assembly while Kenya Kwanza, with the support of seven new members from UDM and 10 independents, could count on the support of 176 members.
No coalition commands an absolute majority of 180 members yet but Ruto is confident that the four elections still pending will swing his coalition's way.
Also, out of the 12 nomination slots that are available, UDA will nominate 5 members which will bring the KKA number in the house to 181. ODM will nominate 4 MPs, while Jubilee will nominate 2 and Wiper 1.
But with more of such moves anticipated as Deputy President-elect Rigathi Gachagua suggests that there were those within Jubilee who were intent on joining Kenya Kwanza, President Uhuru Kenyatta's party is pushing back.
Jubilee Party Secretary General Jeremiah Kioni has warned newly elected leaders against hopping from political outfits through which they were elected on. According to Kioni, leaders who have reportedly begun to shift their allegiance even before the dust from the General Elections settles are dishonest to the people who had voted for them.
"If there will be any migrations, it is the parties which shall sanction such moves in consideration of pre-election agreements that the parties already signed not unless one resigns first," he said.
Speaking in Nakuru after meeting elected Jubilee leaders from the county, Kioni warned that those shifting their allegiance risk losing their seats even before they are sworn in.
"We in Jubilee shall be alert to observe any wayward behaviour among our elected leaders. Those spotted risk losing their seats whether in Parliament or county assembly," said Kioni.
Lawyer Donald Kipkorir also suggested that the defections risked making Kenya a one-party state.
"Only last week, Kenyans in their millions went to vote for their MPs because of their political affiliation or for being Independent. Yet, even before they take their seats, they've defected. Voters have a right to stop them from taking their seats for misrepresentation and fraud," he said.
Ruto had stated at Bomas of Kenya when he was declared winner of the August 9 election that he would "work with the opposition to the extent that they will provide oversight over my administration."
One of the early policy positions that Ruto has said he will take is amending parliamentary standing orders to ensure that Cabinet Secretaries in his administration answer accountability questions in Parliament.
"It has not been possible for Cabinet Secretaries to be interrogated by legislators. Some members of Parliament have been answering questions in Parliament."
"We do not think that is the right thing to do and we are going to have a discussion so that we can adjust and amend the standing orders to make it possible for Cabinet Secretaries to get to the floor of the House and answer questions," Ruto said
Other than that, Ruto built his campaign on undoing some of President Uhuru's policies which will require support from the House.
This majority also serves as an assurance to Ruto's allies such as Ford Kenya leader Moses Wetang'ula who, in the agreement signed to create Kenya Kwanza, was promised the National Assembly Speaker's position.
Those who switched camps were UDM Party Leader and Mandera Senator-elect Ali Roba, Marsabit Governor Mohamud Ali, Mandera Governor-elect Mohamed Adan Khalif.
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Others were Wajir Sen-elect Abbas Sheikh as well as MPs Umulkheir Kassim (Mandera), Bashir Abdullahi (Mandera North), Kullow Hassan (Banisa), Joseph Lekuton (Laisamis), Mangale Munga (Lunga Lunga), Abdi Harow (Mandera South) and Adan Haji (Mandera West)
"Long-standing unresolved issues plus gate keepers feeling threatened by the presence of partners which spilled over into elections. You can't coerce people into loyalty. Engagement was replaced with chest-thumping," Roba said on Thursday via his Twitter.
The former Mandera governor quoted letters his party had addressed to the Registrar of Political Parties in April complaining against the Azimio la Umoja National Council and National Coalition Executive officials
"The party raises concern that it is not being engaged in critical meetings and decisions which bear great impact on the coalition," the letter stated.
Ruto is benefitting from discomfiture that has existed in Azimio la Umoja before the elections. Amason Kingi's Pamoja Africa Alliance (PAA) and Alfred Mutua's Maendeleo Chap Chap were among the first parties to bolt out of the coalition in its formative days and give their support to Kenya Kwanza.
Roba seemed to suggest yesterday that his party suffered from the same problems that other parties in the coalition faced. For instance, it had not received a copy of the coalition agreement documents signed by all parties to the coalition.
"To date, since the formation of the coalition, there has been no engagement with Secretariat in terms of contents, formation and nomination officials to the leadership structure of the coalition. As such we feel aggrieved in the coalition agreement and have lost trust in the Azimio la Umoja One Kenya Alliance," UDM Secretary General David Ohito said then.
Appointments to the Coalition Council and the National Coalition Executive Council, the party said, should be consultative, democratic and transparent.