When mark critz (d) 50.8% tim burns (r) 49.2% are the candidates what is the party?
CREATE TABLE "pennsylvania" (
  "district" text,
  "incumbent" text,
  "party" text,
  "first_elected" real,
  "result" text,
  "candidates" text
);
SELECT "party" FROM "pennsylvania" WHERE "candidates"='Mark Critz (D) 50.8% Tim Burns (R) 49.2%';