Android SQLite - Using where args to delete by _id does NOT delete

When I execute the following, isDeleted is false.

String [] whereArgs = {new Integer(userId).toString()};
boolean isDeleted = db.delete("users_fts", "_id = ?", whereArgs ) > 0;

I have verified that the userId, exists in the users_fts table. (I can do a select). Also, the below query to delete works. isDeleted is true

boolean isDeleted = db.delete("users_fts", "_id = 1361", null ) > 0;

users_fts is a Virtual Table (if that makes any difference).

What is it that I am doing wrong?