Cucumber/Capybara : Cannot check a checkbox (by id, label, value, etc)

Currently, this is the code in my view:

<!-- Renders selected categories as a hash: {"1"=>"Sports", "3"=>"Fashion", "4"=>"World"} -->

  <% unless @categories.nil? %>
    <% @categories.each do |t| %>
      <%= t.name %>
      <%= check_box_tag "categories[#{t.id}]", t.name %>

      <br />
    <% end %>
  <% end %>

This is rendered on a browser, and the respective element on the web page is as follows:

  Entertainment
  <input id="categories_6" name="categories[6]" type="checkbox" value="Entertainment" />

  <br />
  Health
  <input id="categories_5" name="categories[5]" type="checkbox" value="Health" />

  <br />
  Politics
  <input id="categories_3" name="categories[3]" type="checkbox" value="Politics" />

  <br />
  Sports
  <input id="categories_8" name="categories[8]" type="checkbox" value="Sports" />

  <br />
  Tech
  <input id="categories_4" name="categories[4]" type="checkbox" value="Tech" />

  <br />
  Travel
  <input id="categories_7" name="categories[7]" type="checkbox" value="Travel" />

  <br />
  United States
  <input id="categories_1" name="categories[1]" type="checkbox" value="United States" />

  <br />
  World
  <input id="categories_2" name="categories[2]" type="checkbox" value="World" />

  <br />

In my Cucumber test, I would like to be able check categories that I have listed, and as such I have the following as my scenario/steps:

Step:

When /^(?:|I )check "([^"]*)"$/ do |field|
  check(field)
end

Scenario:

@javascript 
Scenario: a signed in user can post an article with an associated category
  Then I should see "Sign out"
  Then I should see "New Article"
  Then I should see "Hello"
  When I follow "New Article"
  And I fill in "Url" with "Hello_World_Article_URL.com"
  And I fill in "Initial comment" with "My first comment"
  And I check "categories_6"
  And I press "Create Article"
  Then I should see "Article created!"
  Then article url "Hello_World_Article_URL.com" should exist

However, this fails at the And I check "categories_6" step, reporting a Capybara ElementNotFound Error. I am unclear as to why referencing the checkbox by "id" did not work correctly. Does anyone have insight into what I may have done incorrectly or how I could go about fixing this issue?

Thanks.