When waikaia is the electorate what is the highest by-election?
CREATE TABLE table_28898948_3 (by_election INTEGER, electorate VARCHAR)
SELECT MAX(by_election) FROM table_28898948_3 WHERE electorate = "Waikaia"
### Context: CREATE TABLE table_28898948_3 (by_election INTEGER, electorate VARCHAR) ### Question: When waikaia is the electorate what is the highest by-election? ### Answer: SELECT MAX(by_election) FROM table_28898948_3 WHERE electorate = "Waikaia"