Martha Karua Effect: Did She Move Votes in Central Kenya?

Martha Karua's selection as Raila Odinga's running mate on May 16, 2022, sent shockwaves through Kenya's political landscape. For the first time in history, a major presidential ticket featured a woman as deputy. Karua — a former Justice Minister, presidential candidate, and fierce anti-corruption crusader — was meant to be the answer to Raila's perennial Mt. Kenya problem. The question after August 9th was simple: did it work?

The Baseline: Raila Without Karua

To measure the 'Karua effect,' we need a baseline. Here's how Raila performed in core Mt. Kenya counties without a Kikuyu running mate:

• 2013 (running mate Kalonzo Musyoka): 3.8% in Kiambu, 2.1% in Murang'a, 3.5% in Nyeri
• 2017 (running mate Kalonzo Musyoka): 16.7% in Kiambu, 9.5% in Murang'a, 13.8% in Nyeri

The 2017 figures were boosted by anti-Jubilee sentiment among some voters. So the relevant comparison is against the 2017 baseline.

The 2022 Results: Marginal Gains

With Karua on the ticket and Uhuru's endorsement, here's what Raila achieved in 2022:

• Kiambu: 26.1% (up from 16.7% in 2017, a gain of +9.4 points)
• Murang'a: 19.5% (up from 9.5%, a gain of +10.0 points)
• Nyeri: 21.9% (up from 13.8%, a gain of +8.1 points)
• Kirinyaga (Karua's home): 25.6% (up from 11.2%, a gain of +14.4 points)
• Nyandarua: 20.5% (up from 8.3%, a gain of +12.2 points)

On the surface, these look like significant improvements — an average gain of 10.8 percentage points across core Central Kenya. But context matters enormously.

Disentangling Karua from Uhuru

The critical question is: how much of the improvement was due to Karua, and how much was due to Uhuru Kenyatta's endorsement and active campaigning for Raila?

There's no clean way to isolate these effects, but several indicators suggest Uhuru was the larger factor:

• Areas where Uhuru personally campaigned (Gatundu South, Gatundu North, Juja) showed larger gains than areas where only Karua campaigned
• Meru and Embu counties — where Karua had minimal personal influence but Uhuru's allies campaigned — showed similar percentage-point gains (+8-9 points)
• Kirinyaga County, Karua's home turf, showed the biggest gain (+14.4 points), suggesting a genuine local effect — but she still lost her home county by a 49-point margin

The Gender Dimension

One undeniable impact of Karua's candidacy was on women voters. Post-election surveys by Infotrak and TIFA Research suggested that:

• Women in Central Kenya were 12-15% more likely to vote for Azimio than men in the same region
• Karua's candidacy increased women's enthusiasm to vote, with turnout among women in Mt. Kenya rising an estimated 3 percentage points compared to 2017
• Among urban, educated women nationally, Karua was cited as the primary reason for supporting Azimio by 23% of respondents

However, these gains were insufficient to overcome the overwhelming male vote for Ruto-Gachagua in the region.

What Karua Cost Azimio

There's an underexplored counter-argument: did Karua actually cost Raila votes elsewhere? Some evidence suggests yes:

• In Ukambani, Kalonzo Musyoka's demotion from running mate to 'chief minister designee' reportedly depressed his campaign enthusiasm, contributing to lower-than-expected turnout in Machakos and Kitui
• In Western Kenya, Musalia Mudavadi's defection to Kenya Kwanza was partly motivated by Raila's perceived favouritism toward Mt. Kenya over Luhya interests
• The Luo Nyanza vote remained solid (95%+) regardless of the running mate — meaning the Karua pick didn't add votes in Raila's base but may have weakened allied bases

The Verdict

The Martha Karua effect was real but modest. She added approximately 200,000-250,000 votes to Raila's Mt. Kenya total compared to a no-Karua baseline — a meaningful number, but nowhere near enough to close the 1.85-million-vote gap that Ruto built in the region.

More importantly, Karua's historic candidacy broke a barrier. The next time a woman runs for deputy president in Kenya, she won't have to carry the weight of being first. That legacy transcends vote counts.

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