WASHINGTON — Top Army officials told a Senate panel today that the Army is under serious strain and must reduce the length of combat tours as soon as possible.

“The cumulative effects of the last six-plus years at war have left our Army out of balance, consumed by the current fight and unable to do the things we know we need to do to properly sustain our all-volunteer force and restore our flexibility for an uncertain future,” the chief of staff of the Army, General George Casey.

General Casey told the Senate Armed Services Committee that cutting the time soldiers spend in combat is an integral part of reducing the stress on the force.

He said he anticipates the service can cut combat tours to 12 months from 15 months this year, so long as the president reduces the number of active-duty Army brigades in Iraq and Afghanistan to 15 units by July as planned.

However, the number of soldiers retained under the service’s “stop loss” policy — which forces some soldiers to stay on beyond their retirement or re-enlistment dates — is unlikely to be reduced substantially.

“We are consuming readiness now, as quickly as we’re building it,” Army Secretary Pete Geren, who also testified, said.

Secretary Geren also urged Congress to pass a $100 billion war spending bill this spring, contending that the Army will run out of money by July.

According to the nonpartisan Congressional Research Service, the Army could probably last until August or September by transferring money from less urgent accounts. Army officials counter that this approach is inefficient and can cause major program disruptions.

The hearing came as the Senate headed toward a vote on whether to cut off money for the Iraq war within 120 days. The measure, by Senator Feingold, Democrat of Wisconsin, was widely expected to fall short of the 60 votes needed to pass.

The Republican leader of the Senate, Mitch McConnell, said the bill is a good chance for the Senate to go on record again as refusing to cut off money for the war.

“All the more so will we oppose it when the fight in Iraq, by all accounts, is showing clear-cut tactical progress, and now, at last, some important political progress is also being made,” Mr. McConnell, Republican of Kentucky, said.

In recent months, violence in Iraq has declined and the Baghdad government has made small steps toward political reconciliation, including plans to hold provincial elections on October 1. While Democratic voters remain largely against the war, the security improvement has helped to cool anxiety among Republicans and stave off legislation demanding that troops start coming home.

With Mr. Feingold’s bill almost assured to fail and lacking a veto-proof majority in Congress even if such a proposal passed, Democrats are talking about whether to shift their strategy. Instead of repeating losing votes on legislation tying money to troop withdrawals, many party members want to focus more on the policy issues surrounding Iraq, including the preparedness of American troops and reining in private contractors.

Another desire by many Democrats is to tie the ailing economy to the war. A coalition of anti-war groups said this week that it plans to spend more than $20 million this year to convince voters that the Republican party’s support for the war is bad for their wallets.

Still, other Democrats, including Mr. Feingold, Democrat of Wisconsin, say they want to pursue more votes to end funding for the war.

According to aides, the majority leader of the Senate, Harry Reid, Democrat of Nevada, who co-sponsored Mr. Feingold’s proposal, agreed to stage today’s vote in exchange for Mr. Feingold’s earlier support of a defense policy bill.