getting date from nullable datetime ?

I have declared a field in my model as nullable datetime like this

public DateTime? CallNextDate {get;set;}

in my aspx code behind I am using this linq like this:

q = q.AsQueryable()
    .Where(c => c.CallNextDate.Date < DateTime.Now.Date )
    .ToList();

but c.CallNextDate.Date is not available. Please suggest how to fix it