Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_1463383_1 (left_bloc VARCHAR, social_democratic VARCHAR)

### Question ###
What are all percentages of Left Block when there is a 28.7% Social Democratic?

### Accurate SQL ###

SELECT left_bloc FROM table_1463383_1 WHERE social_democratic = "28.7%"