When Senator Hillary Rodham Clinton needed help rounding up superdelegates, she turned to Harold M. Ickes, the ultimate Democratic fixer, ... ... Mr. Ickes is also wearing another hat. He is president of Catalist, a for-profit databank that has sold its voter files to the Obama and the Clinton presidential campaigns for their get-out-the-vote efforts. With his equity stake in the firm, Mr. Ickes stands to benefit financially no matter which candidate becomes the Democratic nominee. In creating Catalist, Mr. Ickes, ... has formed a rare entity on the political scene, a for-profit limited-liability corporation that allows wealthy Democratic donors...