MINNEAPOLIS, July 15, 2008—As many had predicted, President Bush Tuesday vetoed the Medicare Improvements for Patients and Providers Act of 2008, with the prospect that the House and Senate would override him today.

The president described the bill, known to many as HR 6331, as "fiscally irresponsible." His opposition is largely due to the damage it does to Medicare Advantage plans, which Bush has strongly supported.

The House, which approved the bill by a vote of 355 to 59 last month is expected to vote quickly to override the veto. It is less certain what will happen in the Senate where nine Republican senators voted for the bill.

The Senate passed the bill by a vote of 69 to 30, which is enough to override a veto—unless some of the nine GOP senators change their votes.

The Senate is likely to act soon after the House does.