My organization is currently running a multi-site CiviCRM deployment on Drupal 7 using the domain access module.
We set permissions on the contacts by using the state field so that the leadership in a state can only see that state's contacts.
Some states also have home pages with custom content and menus, but use the bulk of the national web site as "background" content.
The above configuration has served us well for several years now, but we keep getting push back from states that Drupal is too hard to use and people aren't posting content for that reason.
Can we replicate this same functionality on the WordPress platform? If not, how close can we get?