diff --git a/app/models/poll/voter.rb b/app/models/poll/voter.rb
index 8b0202aee..dd8c85d8f 100644
--- a/app/models/poll/voter.rb
+++ b/app/models/poll/voter.rb
@@ -1,11 +1,13 @@
 class Poll
   class Voter < ActiveRecord::Base
     belongs_to :booth_assignment
-    delegate :poll, to: :booth_assignment
+    belongs_to :poll
 
     validates :booth_assignment, presence: true
     validate :in_census
     validate :has_not_voted
+    validates :poll, presence: true
+    validates :document_number, presence: true, uniqueness: { scope: [:poll_id, :document_type] }
 
     def in_census
       errors.add(:document_number, :not_in_census) unless census_api_response.valid?
diff --git a/db/migrate/20170125104542_add_poll_id_and_stats_fields_to_poll_voter.rb b/db/migrate/20170125104542_add_poll_id_and_stats_fields_to_poll_voter.rb
new file mode 100644
index 000000000..84e7de5d9
--- /dev/null
+++ b/db/migrate/20170125104542_add_poll_id_and_stats_fields_to_poll_voter.rb
@@ -0,0 +1,12 @@
+class AddPollIdAndStatsFieldsToPollVoter < ActiveRecord::Migration
+  def change
+    add_column :poll_voters, :poll_id, :integer,  null: false
+
+    remove_column :poll_voters, :booth_assignment_id, :integer, null: false
+    add_column :poll_voters, :booth_assignment_id, :integer
+
+    add_column :poll_voters, :age, :integer
+    add_column :poll_voters, :gender, :string
+    add_column :poll_voters, :geozone_id, :integer
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index 8eb3c5ce3..0cdbcad2b 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20170120164547) do
+ActiveRecord::Schema.define(version: 20170125104542) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -449,9 +449,13 @@ ActiveRecord::Schema.define(version: 20170120164547) do
   create_table "poll_voters", force: :cascade do |t|
     t.string   "document_number"
     t.string   "document_type"
-    t.integer  "booth_assignment_id", null: false
     t.datetime "created_at",          null: false
     t.datetime "updated_at",          null: false
+    t.integer  "poll_id",             null: false
+    t.integer  "booth_assignment_id"
+    t.integer  "age"
+    t.string   "gender"
+    t.integer  "geozone_id"
   end
 
   create_table "polls", force: :cascade do |t|