diff --git a/.pytest.expect b/.pytest.expect
index 8bfcf4b7..f03e18f8 100644
--- a/.pytest.expect
+++ b/.pytest.expect
@@ -208,51 +208,6 @@ u'html5lib/tests/testdata/tree-construction/isindex.dat::3::cElementTree::parser
 u'html5lib/tests/testdata/tree-construction/isindex.dat::3::cElementTree::parser::void-namespace': FAIL
 u'html5lib/tests/testdata/tree-construction/isindex.dat::3::lxml::parser::namespaced': FAIL
 u'html5lib/tests/testdata/tree-construction/isindex.dat::3::lxml::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::0::DOM::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::0::DOM::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::0::DOM::treewalker': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::0::ElementTree::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::0::ElementTree::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::0::ElementTree::treewalker': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::0::cElementTree::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::0::cElementTree::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::0::cElementTree::treewalker': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::0::genshi::treewalker': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::0::lxml::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::0::lxml::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::0::lxml::treewalker': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::1::DOM::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::1::DOM::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::1::ElementTree::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::1::ElementTree::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::1::cElementTree::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::1::cElementTree::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::1::lxml::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::1::lxml::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::2::DOM::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::2::DOM::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::2::ElementTree::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::2::ElementTree::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::2::cElementTree::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::2::cElementTree::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::2::lxml::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::2::lxml::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::3::DOM::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::3::DOM::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::3::ElementTree::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::3::ElementTree::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::3::cElementTree::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::3::cElementTree::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::3::lxml::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::3::lxml::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::4::DOM::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::4::DOM::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::4::ElementTree::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::4::ElementTree::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::4::cElementTree::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::4::cElementTree::parser::void-namespace': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::4::lxml::parser::namespaced': FAIL
-u'html5lib/tests/testdata/tree-construction/math.dat::4::lxml::parser::void-namespace': FAIL
 u'html5lib/tests/testdata/tree-construction/menuitem-element.dat::3::DOM::parser::namespaced': FAIL
 u'html5lib/tests/testdata/tree-construction/menuitem-element.dat::3::DOM::parser::void-namespace': FAIL
 u'html5lib/tests/testdata/tree-construction/menuitem-element.dat::3::ElementTree::parser::namespaced': FAIL
diff --git a/html5lib/treebuilders/_base.py b/html5lib/treebuilders/_base.py
index 900a724c..a4b2792a 100644
--- a/html5lib/treebuilders/_base.py
+++ b/html5lib/treebuilders/_base.py
@@ -167,12 +167,17 @@ def elementInScope(self, target, variant=None):
         # If we pass a node in we match that. if we pass a string
         # match any node with that name
         exactNode = hasattr(target, "nameTuple")
+        if not exactNode:
+            if isinstance(target, text_type):
+                target = (namespaces["html"], target)
+            assert isinstance(target, tuple)
 
         listElements, invert = listElementsMap[variant]
 
         for node in reversed(self.openElements):
-            if (node.name == target and not exactNode or
-                    node == target and exactNode):
+            if exactNode and node == target:
+                return True
+            elif not exactNode and node.nameTuple == target:
                 return True
             elif (invert ^ (node.nameTuple in listElements)):
                 return False