According to The Huffington Post, in an article published during McCain’s 2008 presidential run, Soros funded the McCain’s Reform Institute, a nonpartisan 501c3 organization focused on promoting accountability and transparency in government, while the senator was still with the organization.
The Huffington Post article also referenced two Talking Points Memo reports: One indicated that Soros gave the Reform Institute $150,000; another said Soros’ Open Society Institute in 2002 gave $300,000 in grants to groups defending McCain’s campaign finance law against legal challenges to it.