The posts in this thread provide some ammunition to present to Congress
in support of extension.  We should also bear in mind that there are
other consequences to the special coverage: federal examiners and
observers.  Experience in recent elections would seem to support
continued availability of both.  

It may be more difficult to convince the Court of the continuing
validity of special coverage than to convince the Congress of the policy
reasons for extension.  The Court is likely to give skeptical review to
each aspect of the special coverage: the coverage formula, the
difficulty of bailout, the requirement of preclearance, the burden on
the submitting jurisdiction to show the change is not discriminatory,
the effects test, the bypass of local federal courts [requiring review
by the DCDC], and the examiner and observer provisions.  So proponents
of extension will need to address each of these aspects as they make a
record before Congress.