The alliance led by Kenyan presidential candidate Raila Odinga will come down hard on corruption if it wins in August, his running mate Martha Karua said, but dismissed her nickname “Iron Lady” as a sexist trope directed at tough women leaders.

“Strong leadership in women is seen as an exception and not the norm because I haven’t heard of an iron man,” the 64-year-old former justice minister said.

Karua and veteran opposition leader Odinga, who heads the Azimio La Umoja One Kenya Alliance coalition, are facing off with deputy president William Ruto and first time lawmaker Rigathi Gachagua in an election on August 9...