json.net won't deserialize string

here is my class:
    public class FeedStatusResultMain
    {

        public long feedstatusid { get; set; }
        public long feedid { get; set; }
        public long clientid { get; set; }
        public string clientname { get; set; }
        public string feedname { get; set; }
        public string feeddescription { get; set; }
        public string direction { get; set; }
        public string status { get; set; }
        public string starttime { get; set; }
        public string endtime { get; set; }
        public string nextrundate { get; set; }
        public int summaryprocessed { get; set; }
        public int summaryloaded { get; set; }
        public int summaryrejected { get; set; }
        public string environment { get; set; }
    }

Here is the json response returned from my web service:
"[{
"feedstatusid":92738,
"feedid":143,
"clientid":2,
"clientname":"client1",
"feedname":"report1",
"feeddescription":"report1",
"direction":"O",
"status":"P",
"starttime":"2014-10-23 10:40:32",
"endtime":"2014-10-23 10:40:37",
"nextrundate":"2014-10-23 10:50:32",
"summaryprocessed":3,
"summaryloaded":0,
"summaryrejected":0,
"environment":""
},
{
"feedstatusid":92737,
"feedid":148,
"clientid":2,
"clientname":"client2",
"feedname":"report2",
"feeddescription":"report2",
"direction":"O",
"status":"P",
"starttime":"2014-10-23 10:40:00",
"endtime":"2014-10-23 10:40:07",
"nextrundate":"2014-10-23 10:50:00",
"summaryprocessed":2,
"summaryloaded":3,
"summaryrejected":0,
"environment":""
}]"

I try to deserialize into a list<FeedStatusResponseMain> like this:
List<FeedStatusResultMain> frx = JsonConvert.DeserializeObject<List<FeedStatusResultMain>>(rx);

it throws the following error:
System.ArgumentException: Could not cast or convert from System.String to System.Collections.Generic.List`1[TMSWebServiceClient.FeedStatusResultMain].

I am going nuts trying to find out why this error is happening.  I've tried the JArray.parse() and JObject.parse() methods, but nothing works, just errors.  I don't see anything wrong with the json and the code is right out of their documentation!