The Reagan administration, as part of its effort to win congressional approval for additional interim funds for the Nicaraguan contras, has decided to ask the Senate to vote on a new $22.8 million aid package, administration and Capitol Hill aides said yesterday.

Under the strategy, based in part on the premise that contra aid is viewed more favorably in the Senate than in the House, Senate Republicans are expected to offer the new proposal as an amendment to an omnibus spending bill. A vote on the bill is expected this week or next.

If the amendment is approved, Senate Republicans hope to persuade House leaders to embrace it in a House-Senate conference on the spending bill.

Republicans Senate aides expressed optimism yesterday that the new plan would win Senate approval, and Democratic Senate staffers also said some form of new contra aid is likely.

Senate Democrats, including Christopher J. Dodd (Conn.), are attempting to produce an alternative that would be more in line with the Central American peace process, aides said.

A key issue is expected to be whether the Central Intelligence Agency, mainly responsible for managing the contra war effort, will be allowed to administer new interim funds.

Democrats have said permitting the CIA to handle such funds would be contrary to the peace process and signify continuation of the war against the Sandinista government.

Administration officials have contended that it would be impractical and impossible to devise an alternative mechanism to deliver supplies to contras inside Nicaragua. "The International Red Cross does not do {air} drops," one official said.

The administration has described its interim assistance requests as "nonlethal aid" that will provide food, clothing and transportation to the contras through February while efforts to complete the peace process are under way.

Congressional Democrats have said the administration, aware that it cannot win new military aid, has adopted the "nonlethal" aid tactic as a device to enable the contras to continue the war.

Congress has approved about $7 million in interim contra aid since Oct. 1, but officials say those funds will run out next Wednesday.

The new proposal for $22.8 million would bar purchase of airplanes and helicopters, which would have been allowed under an earlier $30 million proposal. Under the new proposal, replacement airplanes could be leased instead, an administration official said.

Meanwhile yesterday, the House voted, 215 to 200, generally along party lines, to ban the administration from seeking military aid from other nations for the contras.