diff --git a/Makefile b/Makefile
index d3a83707..9d13cf5b 100644
--- a/Makefile
+++ b/Makefile
@@ -79,7 +79,7 @@ help:
 	@echo ''
 	@echo 'Targets:'
 
-	@awk '/^[a-zA-Z\-\_0-9]+:/ { \
+	@awk '/^[a-zA-Z0-9_-]+:/ { \
 		helpMessage = match(lastLine, /^## (.*)/); \
 		if (helpMessage) { \
 			helpCommand = substr($$1, 0, index($$1, ":")-1); \