The Chicago Symphony Orchestra ran a deficit of $2.3 million on a budget of nearly $58 million in its 2003-04 season. That’s the bad news. But the good news is that the red ink is about $1.7 million less than the CSO had anticipated, and significantly less than the $7 million deficit of a few years ago. Still, the orchestra was forced to withdraw more than $9 million from its endowment in the past year to cover operating costs. The CSO’s management team has pledged a return to balanced budgets by the 2006-07 season.