WASHINGTON - President Bush and congressional Republicans are putting together a tax-cut package designed to spur economic growth next year, hoping to deliver a politically appealing initiative early in the next Congress.

Bolstered by their success in the midterm elections - and their triumphs on major legislation in Congress' postelection session - Republicans are devising a package they say would energize the sluggish economy.

The White House has stayed quiet about the details of any such measure. Officials say Bush is weighing his options but is all but certain to propose some form of tax relief.

"The president hasn't made any decisions," said Claire Buchan, a White House spokeswoman. Bush "is talking to his advisers, and he's reviewing the advice he's being given and looking carefully at economic data."

But privately, congressional Republicans and White House officials have begun discussing leading contenders for inclusion in a tax-cut package.

Among the proposals most likely to be included is one to reduce the taxation of corporate dividends - either by shielding the dividends from corporate taxes or by reducing or eliminating the tax investors pay once they receive the dividends.

The proposal, a favorite of business groups, is gathering support on Capitol Hill and at the White House. Glenn Hubbard, chairman of the Council of Economic Advisers is advancing the idea that a dividend cut would be the most effective way to quickly stimulate the economy, people familiar with his thinking say.

Proponents complain that dividends are essentially taxed twice - once when companies pay taxes on earnings and again when dividends paid to shareholders are taxed as income.

Even some Democrats - most recently Sen. John Kerry of Massachusetts, a presidential hopeful - have endorsed a dividend tax cut as well as other tax relief.

But other Democrats argue that wealthy investors would benefit disproportionately from a dividend tax cut. They say Congress should focus on helping low- and middle-income Americans through improved unemployment benefits and targeted tax cuts.

The idea of a dividend tax cut has gained currency with Washington's renewed focus on corporate accountability. In recent years, as companies increasingly sought to boost their stock prices rather than to pay out dividends, some economists say, the potential for corporate wrongdoing and misleading accounting rose.

Reducing or eliminating the taxation of dividends is just one of a long list of tax cuts that officials and lawmakers are considering as part of an economic relief measure. Such a plan is expected to be a marquee agenda item of the 108th Congress, which convenes next month.

"I expect [the administration] to trot it out very quickly," a senior Republican Senate aide said of the tax package. "I think they are sort of seizing the moment and trying to move forward as quickly as possible to keep the momentum going from the elections."

The tax-cut measure would be similar to the "stimulus" bill that Bush and lawmakers in both parties called for after the Sept. 11 attacks, when the economy was in the depths of a profound slump, and that Congress approved in March after intense political wrangling.

That measure included an extension of jobless benefits and investment incentives for businesses, including the ability to write off the cost of equipment purchases more quickly.

This time, White House officials are stressing that their goal is not merely to provide a quick infusion to a flagging economy, but rather to create jobs and growth that would bolster a long-term recovery.

Bush has focused his tax-cutting rhetoric this year mostly on his longtime goal of making his $1.35 trillion tax cut, much of which expires at the end of 2010, permanent.

"In order to make sure our economy is strong and vibrant, we better make sure the tax cuts are permanent," the president said this week during a campaign stop in Louisiana.

While White House officials work to put together their plan, top Republican tax-writers in Congress are holding back, at least for now, on proposing their own ideas. They are letting Bush - whom they credit with engineering their party's election successes - take the lead.

Bush administration officials have met in recent weeks with congressional aides to discuss potential elements of the tax relief package, staffers say. Such a package would most likely include a mix of incentives intended to encourage spending and investing.

With the idea of putting more money in consumers' pockets, some lawmakers in both parties are focusing on a proposal to temporarily eliminate the payroll taxes that employers and workers pay on a portion of wages.

Many Republicans have also proposed accelerating elements of the 2001 tax cut that are scheduled to take effect in 2004, including individual income tax-rate cuts, tax cuts for married couples, or an increase in the child tax credit.

Some Democrats are considering calling for another round of tax rebate checks. The beneficiaries could include low- and middle-income individuals who pay no income tax but are likely to spend a one-time cash infusion, thus pumping the money back into the economy.

House Democrats are expected to debate dozens of proposals among themselves next week at a two-day caucus focusing on the economy.

In advance of a Congress whose agenda will be dictated by Bush and controlled in both chambers by conservative Republicans, Democrats will begin tackling a difficult quandary: how to promote their own economic ideas without throwing cold water on what is certain to be a politically popular Republican tax-cutting agenda.

"I don't have a lot of confidence in their concern with the economic short term," said Rep. Benjamin L. Cardin, a Baltimore Democrat who is a senior member of the tax-writing Ways and Means Committee. "In my view, it's just using the poor performance of the economy to justify tax cuts."

The Business Roundtable, a leading interest group, called last month for a $300 billion tax-cut package. It would include a one-year elimination of payroll taxes on the first $10,000 of wages, an acceleration of individual income tax cuts and a reduction in dividend taxation for individuals.

While there is no shortage of tax-cutting proposals on the table, the shape of any package will be dictated in large part by the portion of a deficit-plagued federal budget that Bush is willing to devote to the measure.

That figure, tax analysts and aides say, will make clear to lawmakers how much leeway they have to pay for the various competing proposals and will force them to modify or eliminate some.

"We're still in the trial-balloon stage," said Clint Stretch, director of tax policy for the accounting firm Deloitte & Touche.

The dividend proposal, which economists estimate could cost $25 billion or more a year, is a good example, Stretch said:

"Every academic tax policy person would say double taxation of corporate earnings is bad policy. But when we get to the end of the day, the question will be, do we give dividend relief, or do we give relief to widows and orphans?"

Sun staff writer David L. Greene contributed to this article.