My reasoning may be flawed, but I would think that any state that voted for Obama would not need to use the VRA to create African American majority-minority districts because white racists in the state are obviously outweighed by people willing to vote for a black president.
Perhaps if the US used proportional representation to elect its state legislatures, but obviously not in current circumstances.
Even so, the VRA is about the preferred candidate of minority voters, not minority candidates themselves. The question is whether minority-preferred candidates can be consistently elected (and in rough proportion to minorities' population figures), not whether minorities themselves can be elected. Thus it is not a VRA violation when TN-09 consistently votes in a white representative because he's winning most of the black vote, but it is when a candidate (of any race) wins a substantially minority seat without winning some significant portion of the minority vote, and that election is more than just a fluke.[1] (Exactly what proportion is necessary to pass this threshold has been of some debate, mostly WRT Hispanic voters, who are less monolithically partisan than black voters, but that's a side issue.)
Since that's the question, you should be asking whether those states consistently elect minority-preferred candidates (and not just for President, but for other offices as well).
Consistently is a key term--electing the occasional minority-preferred candidate but mostly electing candidates not receiving a significant portion of the minority vote is not enough.
Of course, none of the states in question are as a whole minority-majority, so the real issue are regions within the states.
[1]So the fact that Anh Cao could be elected while receiving very few black votes didn't mean his seat needed to be made more heavily black to comply with the VRA, as long as the seat elected the preferred black candidate most of the time, as it has.
