CREATE TABLE table_3629 ("District" TEXT, "Incumbent" TEXT, "Party" TEXT, "First elected" TEXT, "Result" TEXT, "Candidates" TEXT)

What is the district with the candidates edwin gray (dr)?
SELECT "District" FROM table_3629 WHERE "Candidates" = 'Edwin Gray (DR)'
SELECT "District" FROM "table_3629" WHERE "Candidates" = 'Edwin Gray (DR)'