Name the poll source for republican joe kenney being 28%
CREATE TABLE table_21787 (
    "Poll Source" text,
    "Dates administered" text,
    "Democrat: John Lynch" text,
    "Republican: Joe Kenney" text,
    "Lead Margin" real
)
SELECT "Poll Source" FROM table_21787 WHERE "Republican: Joe Kenney" = '28%'
Below are sql tables schemas paired with instruction that describes a task. Using valid SQLite, write a response that appropriately completes the request for the provided tables. ### Instruction: Name the poll source for republican joe kenney being 28% ### Input: CREATE TABLE table_21787 (
    "Poll Source" text,
    "Dates administered" text,
    "Democrat: John Lynch" text,
    "Republican: Joe Kenney" text,
    "Lead Margin" real
) ### Response: SELECT "Poll Source" FROM table_21787 WHERE "Republican: Joe Kenney" = '28%'