" He is undoubtedly a successful politician,” says George Pagoulatos, professor of European politics and economy at the Athens University of Economics and one of Syriza’s most vocal critics. “His political positioning aside, he took a party from 4 percent [into] government, winning elections and referendums. And he won in September 2015, running on the opposite platform [than he did in] January.”
http://www.politico.eu/article/alexis-tsipras-the-escapologist-grece-austerity/