WASHINGTON, Aug 5 (Reuters) - The $1 trillion bipartisan infrastructure bill being debated in the U.S. Senate would increase federal budget deficits by $256.1 billion over 10 years, the Congressional Budget Office said on Thursday, leaving the measure well short of calls by some lawmakers that it be fully paid for.

The long-awaited CBO cost estimate, which could influence support in the evenly divided Senate, found that the Infrastructure Investment and Jobs Act would increase discretionary spending by $415.5 billion and increase revenues by $49.7 billion, compared to the baseline of existing laws. It also would decrease direct spending by $109.6 billion compared to that baseline, CBO said. (Reporting by David Lawder; Editing by Leslie Adler)