Vertically Align Bootstrap Checkbox

I'm trying to vertically align checkboxes for a column of checkboxes + labels. Ideally, I'd like the elements to be in the center of the page but with the checkboxes themselves vertically aligned.

<div class="row">
  <div class="span12 pagination-centered">
  <div class="checkbox">
    <label><input type="checkbox" value="">asdfasdf</label>
  </div>
    <div class="checkbox">
    <label><input type="checkbox" value="">sdfasdf</label>
  </div>
  <div class="checkbox">
    <label><input type="checkbox" value="">asfdasdf</label>
  </div>
  <div class="checkbox">
    <label><input type="checkbox" value="">asdfasdf</label>
  </div>
 </div>
</div>