I have a list like this:

<ul>
    <li id="adm-thumb" onclick="javascript:addBanner('bowling.jpg');">
     <div class="adm-tick"></div>
       <img src="img/banners/bowling.jpg" /></li>

    <li id="adm-thumb" onclick="javascript:addBanner('kcc.jpg');">
     <div class="adm-tick"></div>
       <img src="img/banners/kcc.jpg" /></li>

    <li id="adm-thumb" onclick="javascript:addBanner('paintballing.png');">
     <div class="adm-tick"></div>
       <img src="img/banners/paintballing.png" /></li>
</ul>

<input id="bannername" type="text" />

When one item is clicked, the value inside the addBanner() will be added to the input field, however, I want one list to be selected (which is done by css to make it look like it has) when it is equal to the value of the input value. If the value is equals to the value in the addBanner value then the clicked item should have a red background.

e.g.

function addBanner(label)
{
 var Field = document.getElementById('bannername');
 Field.value = label;

 if(Field.value != label)
 {
     // I have no idea what to put here
 }
}

Something like a div button that acts like a radio button.