JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://merkd.com/engine/ui/themes/lux/assets/js/jquery-2.1.4.min.js"></script>
<script src="https://merkd.com/engine/ui/themes/lux/assets/js/jquery-ui.min.js"></script>
<script src="https://merkd.com/engine/ui/themes/lux/assets/js/moment.js"></script>
<script src="https://merkd.com/engine/ui/themes/lux/assets/js/bootstrap.js"></script>
<link rel="stylesheet" href="https://merkd.com/engine/ui/themes/lux/assets/css/bootstrap.css">
<script src="https://merkd.com/engine/ui/themes/lux/assets/js/bootstrap-datetimepicker.min.js"></script>
<link rel="stylesheet" href="https://merkd.com/engine/ui/themes/lux/assets/css/bootstrap-datetimepicker.min.css">
<link rel="stylesheet" href="https://merkd.com/engine/ui/themes/lux/assets/css/style.challenges.css">
<!--
From https://merkd.com/challenges/10/details
Line 484
-->
<div class="new-challenge-date-container">
    <img src="merkd.com/engine/ui/themes/lux/assets/images/calendar.png" alt="Date &amp; Time" title="Date &amp; Time" />
    <input type="text" id="new-challenge-date-time-picker" data-preset="03/21/2016 11:31 PM" data-format="MM/DD/YYYY HH:mm:ss A"  />
</div>

JavaScript

//from top of 
//merkd.com/engine/ui/themes/lux/assets/js/main.challenges.js
if ( $('#new-challenge-date-time-picker').length ) {

    var
    datePreset = $('#new-challenge-date-time-picker').attr('data-preset'),
    dateFormat = $('#new-challenge-date-time-picker').attr('data-format');//,
    dateParts = datePreset.split(' '),
    dateString = dateParts[0],
    dateTime = dateParts[1],
    dateTimeParts = dateTime.split(':'),
    dateHour = dateTimeParts[0],
    dateMinutes = dateTimeParts[1],
    dateAMPM = dateParts[2],
    dateStringParts = dateString.split('/'),
    dateMonth = dateStringParts[0],
    dateDay = dateStringParts[1],
    dateYear = dateStringParts[2],
    time = (dateAMPM == 'PM') ? (parseInt(dateHour)+12) + ':' + dateMinutes : dateHour+':'+dateMinutes;
    time += ':00'; // add seconds column
    console.log('Recalculated date/time: '+dateYear+'-'+dateMonth+'-'+dateDay+'T'+time);
    var dateObj = new Date(dateYear+'-'+dateMonth+'-'+dateDay+'T'+time);


    console.log('Preset date: '+datePreset);
    console.log('Preset format: '+dateFormat);

    $('#new-challenge-date-time-picker').datetimepicker({
        minDate: moment(),
        defaultDate: dateObj
        //moment(datePreset, dateFormat)
        // neither works
    });

    $('.new-challenge-date-container img').click(function() {
        $('#new-challenge-date-time-picker').data("DateTimePicker").toggle();
    });
}