"[h]e [Paul Manafort] created the image of Yanukovych as a candidate who would defend the interests of the Russian-speaking population, thus provoking a split in the society, as before that the topic of language had never been important"
with the electoral maps here. And note that Manafort was not involved in any Ukrainian elections before 2006 (according to Leschenko himself).
Good observation. Consistent with that, in the first link I quoted in Post #6, Manafort alludes to the political divisions in the Ukraine, some of which he says break down along east-west lines.