How did Obama change Federalism in USA?

His Administration had Considerably Blurred the lines more between the Federal Government and State Government. -Obamacare made States provide 'Healthcare Exchanges' but the Details of they are Set up and ran are given for the States Responsibility -1/3 of the $787 Billion after 2008 was given to State Governments to Spend. This was huge -SCOTUS protected States Powers in some Cases (Gun Control) while also protecting Federal Government (Obamacare and Same-Sex Marriage)