$form['date'] = array(
  '#prefix'=>t('When do you want to start the featured campaign?'),
  '#date_format' => 'Y-m-d',
  '#date_year_range' => '0:+1',
  '#type' => 'date_popup',
  '#weight'=>0
  );

$form['date'] = array(
  '#prefix'=>t('When do you want to start the featured campaign?'),
  '#date_format' => 'Y-m-d',
  '#date_year_range' => '0:+1',
  '#type' => 'date_popup',
  '#weight'=>0,
  '#datepicker_options' => array('minDate' => 0),
);