Christian Mingle (ChristianMingle.com - formerly Relationships.com) is found on many Christian dating sites like this one as a recommended site. Howevever, I do NOT recommend Christian Mingle as a Christian dating site.
It has been documented by other Websites on the Internet that Spark Networks, the company that owns ChristianMingle.com has a history of supporting g-a-y and l-e-s-b-i-a-n relationships and sex outside of marriage, therefore I strongly recommend that Christians NOT use ChristianMingle.com. See the following links for more information:
http://www.onlinedatingmagazine.com/news2006/glimpseclosesdown.html
http://www.jvalley.org/jcn/02_2006/jdate.html
http://www.christiandatingwatchdog.com/relationships.com.html
Note the Christian Mingle (christianmingle.com) is the same as Relationships.com. They started as ChristianMingle.com, then switched to Relationships.com, and are now back to Christian Mingle.