Congressional Republicans' opposition to any tax rate hike on the top two percent of earners shows few signs of letting up as the debate wears on. But the beneficiaries of that opposition, the nation's wealthiest executives, have themselves begun opening up to the possibility of a rate hike.

On Tuesday, FedEx Chairman and CEO Fred Smith, an adviser to Sen. John McCain's presidential campaign, said that the notion that tax hikes on the richest Americans would kill jobs was simply "mythology."