<script>
function job_list()
{
    jQuery.ajax({
        url: jobvite.ajaxurl,
        data: ({action : 'jobvite_jobs'}),
        dataType: 'json',
        success: function(data) {
            return data;
        }
    });
}
</script>

<script type="text/template" id="careerTemplate">
...
<label>Filter Listings</label>
<select id="departmentSelect">
    <% _.each(job_list().jobs, function(job, val) { %>
        <option><%= job.department %></option>
    <% } %>
</select>
<select id="categorySelect">
    <% _.each(job_list().jobs, function(job, val) { %>
        <option><%= job.category %></option>
    <% } %>
</select>
<select id="locationSelect">
    <% _.each(job_list().jobs, function(job, val) { %>
        <option><%= job.location %></option>
    <% } %>
</select>
...
</script>