Mandela and Obama

After the news of Mandela's death US liberal media just could not help themselves to compare him to Obama.

• Washington Post: Mandela's cause shaped Obama's political awakening
• Obama’s Path Was Shaped by Mandela’s Story
• Mandela's Powerful Influence On Barack Obama

It is being implied that Obama was inspired by Mandela. However, at least one website disagrees:
TOP 5 WAYS BARACK OBAMA IS NO NELSON MANDELA