The budget deficit for the current year is projected to come in well below what was estimated just a few months ago, according to a U.S. government study released Tuesday. The Congressional Budget Office cites higher tax revenues and better-than-expected bailout repayments by mortgage giants Fannie Mae and Freddie Mac as the key reasons for the improved outlook. The budget office now predicts a 2013 budget deficit of $642 billion, more than $200 billion below its February estimate. This year\'s shortfall would register at 4.0 percent of the economy, far less than the 10.1 percent experienced in 2009 when the government ran a record $1.4 trillion deficit. Last year\'s deficit was $1.1 trillion, capping four consecutive trillion dollar-plus deficits during President Barack Obama\'s first term. The deficit picture is expected to continue to improve next year and beyond, with the 2015 deficit now projected at $378 billion, just 2.1 percent of the economy. All told, the budget office predicts deficits over the coming decade of $6.3 trillion, down $522 billion from earlier projections. The CBO report comes as Washington has again hit budget gridlock after enacting a $600 billion-plus tax increase on upper-bracket earners in January. The report could sap momentum from further deficit-cutting efforts. One of the reasons for the burst of additional income tax revenues, the budget office says, is that upper-income taxpayers claimed more income late last year in order to avoid paying the higher tax rates enacted in January.