You needn't look far to find skepticism about the potential of foundations and philanthropists to bankroll the work that newspapers have long done. Conventional wisdom is that funders of nonprofits can make only a marginal difference, that the real answers will come from private sector innovators. But these skeptics aren't much found in evidence at the nation's leading investigative reporting nonprofits. The Center for Public Integrity (CPI), ProPublica and the Center for Investigative Reporting are all on the move, all seeing growing opportunities for nonprofit investigative work, all hopeful about future funding…….