diff --git a/alembic/script/base.py b/alembic/script/base.py
index 7930fe14..e508f580 100644
--- a/alembic/script/base.py
+++ b/alembic/script/base.py
@@ -44,9 +44,9 @@
 _legacy_rev = re.compile(r"([a-f0-9]+)\.py$")
 _slug_re = re.compile(r"\w+")
 _default_file_template = "%(rev)s_%(slug)s"
-_split_on_space_comma = re.compile(r", *|(?: +)")
+_split_on_space_comma = re.compile(r",\s*|(?:\s+)")
 
-_split_on_space_comma_colon = re.compile(r", *|(?: +)|\:")
+_split_on_space_comma_colon = re.compile(r",\s*|(?:\s+)|\:")
 
 
 class ScriptDirectory: