A recent federal investigation into Fannie Mae’s lobbying efforts apparently spurred the GSE to shut down the political activities of its regional outreach offices. But observers question whether current regulations are enough to permanently reduce Fannie lobbying efforts. “If [Fannie’s regional lobbying efforts] can be challenged legally – or even by skirting the edge of the line [of legally acceptable activity], then I think they’ll hesitate to get back involved,” said John Brown, an…