In how many counties di McCain win 41.62% of the vote?
CREATE TABLE "by_county_city" (
  "county" text,
  "obamapct" text,
  "obamanum" real,
  "mc_cainpct" text,
  "mc_cainnum" real
);
SELECT COUNT("county") FROM "by_county_city" WHERE "mc_cainpct"='41.62%';