JSFiddle - React, Tailwind, and code Playground
by mischa
HTML
<html>
<head>
</head>
<body>
<label for='alpha'><input type='checkbox' id='alpha' value='tester'/><span>tester (alpha)</span></label>
</body>
</html>
JavaScript
var contactEl = $('input:checkbox[id="alpha"]');
contactEl.prop('checked', true);