I’m trying to make an thumbnail gallery (2×2) with twitter bootstrap, but I’m not getting the desired effect. in 1st thumbnail of each line, from line 2, is applied to the left margin, making it only fits one image per line.

the code:
<div class="row-fluid">
<div class="span6">
<h2 id="clients">Clients</h2>
<div class="row-fluid">
<ul class="thumbnails">
<li class="span6">
<a href="#" class="thumbnail"><img src="http://placehold.it/220x100" alt=""></a>
</li>
<li class="span6">
<a href="#" class="thumbnail"><img src="http://placehold.it/220x100" alt=""></a>
</li>
<li class="span6">
<a href="#" class="thumbnail"><img src="http://placehold.it/220x100" alt=""></a>
</li>
<li class="span6">
<a href="#" class="thumbnail"><img src="http://placehold.it/220x100" alt=""></a>
</li>
</ul>
</div>
</div>
<div class="span6">
<h2 id="testiominals">Testemunhos</h2>
<blockquote>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.</p>
<small>Someone famous <a href=""><cite title="Source Title">Source Title</cite></a></small>
</blockquote>
<blockquote>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.</p>
<small>Someone famous <a href=""><cite title="Source Title">Source Title</cite></a></small>
</blockquote>
<blockquote>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.</p>
<small>Someone famous <a href=""><cite title="Source Title">Source Title</cite></a></small>
</blockquote>
</div>
</div>
What about multiple rows? Code below; fiddle here.