Size partitions by contributions amount, rather than count.
Add candidate name to tooltips.
Show direction of money flow in tooltip.
Save search criteria internally as jenky s-expression of field-val pairs.
Handle search parameters as a weak s-expression of search inputs.
Add multiple query filter criteria. (Contributor Name and Zip Code)

This could be way more generalizable.
Allow arbitrary fields in select statement.
Allow search criteria across multiple fields.
Move contribution entity query code to own ns.
Add other relevant search fields.
Reorder search fields in select drop down.