MVC 4 asp.net additional parameter to LoginModel

Question

I m a newbie for MVC 4 .net and is stuck in a problem. In LoginModel, I have added an additional parameter as Usertype:

 [Display(Name = "User type")]

 public int UserType { get; set; }

But, when I visit here, 'Login(LoginModel model, string returnUrl)', Usertype is always null and ModelState.IsValid returns false.

Am I missing something, please help.