Powerful House Democrats are eyeing proposals to overhaul the nation’s $3 trillion 401(k) system, including the elimination of most of the $80 billion in annual tax breaks that 401(k) investors receive. House Education and Labor Committee Chairman George Miller, D-California, and Rep. Jim McDermott, D-Washington, chairman of the House Ways and Means Committee’s Subcommittee on Income Security and Family Support, are looking at redirecting those tax breaks to a new system of guaranteed retirement accounts to which all workers would be obliged to contribute. A plan by Teresa Ghilarducci, professor of economic-policy analysis at the New School for Social Research...