If I have correctly understood, you have contacts in one or more column (from c1 to c8).
If so, try to rewrite your SQL statement like the following:
SELECT C1
FROM TABLE
WHERE STATE IN (...)
UNION
SELECT C2
FROM TABLE
WHERE STATE IN (...)
...
UNION
SELECT C8
FROM TABLE
WHERE STATE IN (...)
The UNION operator eliminates duplicates by itself.
I hope this helps you....