The effect of the Norwood amendment
Before the House leadership suddenly stopped the consideration of the Voting Rights Act renewal yesterday, the Rules Committee had adopted a rule allowing only two amendments. The substance of the two amendments can be found here.
The Norwood amendment contains an "updated formula [which] would be a rolling test based off of the last three presidential elections. Any state would be subject to Section 5 if it currently has a discriminatory test in place or voter turnout of less than 50% in any of the three most recent presidential elections." The text of the amendment makes clear that this is 50% of the citizen voting age population (CVAP).
Let's check on which states would be covered under that half of the formula. The Census Bureau publishes information after each federal election on the CVAP turnout. The three most recent are 2004, 2000, and 1996. (For the first two, look for Table 4C). This means the States that would be covered would be Georgia (1996) and Hawaii (1996, 2000). If someone can point me to a source of sub-state data, I can see if any subdivisions of states would be covered.
After a bit more research, I may be able to give you a report on the "discriminatory test" half of the proposed trigger.
Update: Thanks to Dan Levitas for correcting my misreading of the Georgia data.