diff --git a/pardot/resource.py b/pardot/resource.py
index 6da2083..4eda64c 100644
--- a/pardot/resource.py
+++ b/pardot/resource.py
@@ -211,6 +211,8 @@ def get_response_content(self, request, **kwargs):
             self.login()
 
         payload['api_key'] = self.api_key
+        # Need to drop email so it won't confuse Pardot.
+        payload.pop('email')
 
         # run the request and retry once if the request fails with a
         # login error (Pardot API error code '1')
diff --git a/setup.py b/setup.py
index 45be7cf..18d849e 100644
--- a/setup.py
+++ b/setup.py
@@ -12,7 +12,7 @@
     install_requires=[
         'hammock==0.2.4',
         'pprintpp==0.3.0',
-        'six==1.10.0',
+        'six>=1.11.0',
     ],
     test_suite='nose.collector',
     tests_require=['nose', 'responses'],