diff --git a/IPython/core/inputtransformer.py b/IPython/core/inputtransformer.py
index f20b1a1..2c379dd 100644
--- a/IPython/core/inputtransformer.py
+++ b/IPython/core/inputtransformer.py
@@ -461,7 +461,7 @@ def classic_prompt():
 def ipy_prompt():
     """Strip IPython's In [1]:/...: prompts."""
     # FIXME: non-capturing version (?:...) usable?
-    prompt_re = re.compile(r'^(In \[\d+\]: |\ {3,}\.{3,}: )')
+    prompt_re = re.compile(r'^(In \[\d+\]: |\s*\.{3,}: )')
     return _strip_prompts(prompt_re)
 
 
diff --git a/IPython/core/tests/test_inputtransformer.py b/IPython/core/tests/test_inputtransformer.py
index ff136e2..bb5b576 100644
--- a/IPython/core/tests/test_inputtransformer.py
+++ b/IPython/core/tests/test_inputtransformer.py
@@ -228,6 +228,11 @@ syntax_ml = \
           ('    ...:     print i','    print i'),
           ('    ...: ', ''),
           ],
+         [('In [24]: for i in range(10):','for i in range(10):'),
+          # Sometimes whitespace preceding '...' has been removed (issue #6674)
+          ('...:     print i','    print i'),
+          ('...: ', ''),
+          ],
          [('In [2]: a="""','a="""'),
           ('   ...: 123"""','123"""'),
           ],