diff --git a/google_web_fonts.gemspec b/google_web_fonts.gemspec
index 2df27e0..e4b209c 100644
--- a/google_web_fonts.gemspec
+++ b/google_web_fonts.gemspec
@@ -17,7 +17,7 @@ Gem::Specification.new do |s|
   s.test_files = Dir["test/**/*"]
 
   #s.add_dependency "rails", "~> 4.0.2"
-  s.add_dependency "rails", "~> 3.2.16"
+  s.add_dependency "rails", "~> 4.0.0"
 
   s.add_development_dependency "sqlite3"
 end