- Updated March 29, 2012, 9:42 p.m. ET
BY MARK MAREMONT
President Barack Obama’s re-election campaign called on Republican front-runner Mitt Romney to release his tax returns dating back to the 1980s, to see if they contain information about an uncommon investment arrangement at his former private-equity firm that may have helped swell his individual retirement account.
The request follows a page-one article in The Wall Street Journal on Thursday that recounted how employees at the firm, Bain Capital, …