I think what OP is asking is if the forward/mask or iframe a domain name would it rank in the search engines. I have seen it done with keyword rich domain names and (very) long tail search terms and lots of back links, but I do not think it can happen with a competitive term (ie credit cards).
I have included a redirect script below if you want to try it and see how it goes. Just change the info, save it as index.php and upload it to your hosting
Code:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<title>Title</title>
<meta name="keyword" content="keywords">
<meta name="description" content="description.">
</head>
<frameset rows="100%,*" border="0">
<frame src="http://www.domaintoforwardto.com" frameborder="0" />
<frame frameborder="0" noresize="noresize" />
</frameset>
<!-- pageok -->
<!-- 01 -->
<!-- 7.0-->
</html>