The average blue district awards one convention delegate per 28,912 Romney voters, while the average red district awards one delegate per every 56,714 Romney voters. Thanks to this disparity, if a hard-right candidate like Cruz dominates deeply red Southern districts in the SEC primary, a more electable candidate like Rubio could quickly erase that deficit by quietly piling up smaller raw-vote wins in more liberal urban and coastal districts.
The RNC partially compensates for this imbalance in the way it awards delegates on a statewide basis. Republicans award “bonus” delegates to states with lots of GOP officeholders and states with the best GOP performance in the last election. For example, despite both states having nine congressional districts, Tennessee will send 58 delegates to the Cleveland convention while Massachusetts will send 42.
But the bigger boon to Rubio, Bush and other moderates is that the opinions of GOP voters in places like Massachusetts count at all in this process — in an era when the Bay State sends zero Republicans to Congress. It’s a huge factor that many pundits tend to overlook, and it’s why the temperament and qualities that the broader party looks for in a nominee differ so much from those of the loudest and most ideological Freedom Caucus types in Washington.