What party did the incumbent from the Illinois 12 district belong to? 
CREATE TABLE table_1341707_15 (party VARCHAR, district VARCHAR)
SELECT party FROM table_1341707_15 WHERE district = "Illinois 12"
### Context: CREATE TABLE table_1341707_15 (party VARCHAR, district VARCHAR) ### Question: What party did the incumbent from the Illinois 12 district belong to?  ### Answer: SELECT party FROM table_1341707_15 WHERE district = "Illinois 12"