There are mere weeks left to maneuver to keep as much of your money as possible without overpaying taxes for 2012.

But since you don't know whether Congress will save you from a tax increase or let your taxes go up on Jan. 1, any move you make between now and the end of this year may turn out to be less than optimal later.

The reason, of course, is the fiscal cliff and the potential for raising the average middle-class household's taxes $2,200 next year or more if Congress doesn't step up by Dec. 31 to block the proposals.

Even a married couple with income of $17,400 or less might no longer be in the 10 percent tax bracket, which would disappear Jan. 1, and might be bumped up to 15 percent.

Likewise, if you have been in the 10 percent or 15 percent bracket and paying nothing for capital gains on the stocks, bonds, real estate or other investments that provide your retirement income, you might start paying 15 percent. The highest earners might pay 23.8 percent.

Relief on college tuition could be ratcheted down. The $1,000-per-child tax credit could drop to $500, and help for day-care expenses could be cut.

Lowest-income taxpayers could face a 15 percent rate on dividends; those at the highest income could face 43.4 percent. That would include a new 3.8 percent Medicare surtax on investments for high-income people.

Changes could be coming

In all, there could be about 70 tax-related changes if Congress doesn't stop them - though , as taxpayers start seeing the impact on their paychecks, they might call for relief and politicians might make some retroactive changes.

"Normally, you'd be postponing income and accelerating deductions into 2012," said Mark Luscombe, a tax analyst with accounting-services firm CCH. But since next year's taxes now look like they could be higher than this year's, tax advisers are telling many people (especially wealthier ones) to take the income in 2012, when taxes might be lower. Then, in 2013, try to take as many deductions as possible to whittle down the tax bill.

Of course, that plan could go awry, too, if Congress gets into "loophole-closing."

Under some proposals, you could lose some or all of your mortgage deduction, deductions for charitable contributions, and even the deduction for contributions to your 401(k). At this point, it's all talk, and the loophole cutting seems more likely to hit singles earning more than $200,000 and couples earning more than $250,000.

Capital gains

Take capital gains now, advisers suggest, if it makes sense based on the investment, rather than taking the gain next year, when it could be more costly at tax time.

Financial planner Francine Duke has had clients sell some dividend-paying stocks that they've owned for more than a year in taxable accounts and buy them back instead in IRAs, whose dividends are not taxed.

Still, before selling investments and playing with deductions, Luscombe says, people should make sure they do not accidentally push themselves into the higher alternative minimum tax for 2012.

Certain deductions that can be helpful in keeping tax bills low are worthless if you are in the AMT. Among them are deductions you get for paying state income taxes, local property taxes, or mortgage interest. In a year when you are going to be in the AMT, it's best, if possible, to delay paying taxes and mortgages in December and pay them in January.