You can build a Zone Definition for 50 States plus DC with:
INSERT INTO geo_zones (geo_zone_id, geo_zone_name, geo_zone_description, last_modified, date_added) VALUES (40, 'US - 50 states plus DC', 'All 50 states plus DC', NULL, '2008-11-25');
INSERT INTO zones_to_geo_zones (zone_country_id, zone_id, geo_zone_id) VALUES
(223,1, 40),
(223,2, 40),
(223,4, 40),
(223,5, 40),
(223,12, 40),
(223,13, 40),
(223,14, 40),
(223,15, 40),
(223,16, 40),
(223,18, 40),
(223,19, 40),
(223,21, 40),
(223,22, 40),
(223,23, 40),
(223,24, 40),
(223,25, 40),
(223,26, 40),
(223,27, 40),
(223,28, 40),
(223,29, 40),
(223,31, 40),
(223,32, 40),
(223,33, 40),
(223,34, 40),
(223,35, 40),
(223,36, 40),
(223,37, 40),
(223,38, 40),
(223,39, 40),
(223,40, 40),
(223,41, 40),
(223,42, 40),
(223,43, 40),
(223,44, 40),
(223,45, 40),
(223,47, 40),
(223,48, 40),
(223,49, 40),
(223,51, 40),
(223,53, 40),
(223,54, 40),
(223,55, 40),
(223,56, 40),
(223,57, 40),
(223,58, 40),
(223,59, 40),
(223,61, 40),
(223,62, 40),
(223,63, 40),
(223,64, 40),
(223,65, 40);
which can be run in the Tools ... Install SQL Patches ...
Then, go to the Zone Definitions and click on DETAILS for this new Zone and add Canada for All Zones to this Definition ...