Texans who itemize their federal tax returns are only a president's signature away from being able to deduct the state's sales tax.

State officials expect the average Texas family to save $310 a year under a measure passed Monday by the Senate. The deduction would start this year but expire after 2005 unless Congress renews the provision.

The provision is part of a wide-ranging $137 billion corporate tax package.

It provides $76.5 billion in tax breaks for manufacturers – including oil and gas businesses – architectural and engineering firms, and film and music companies. It also includes a $10.1 billion buyout for tobacco farmers and aligns U.S. exporters with international trade rules.

Residents of all 50 states who itemize their federal taxes would be able to deduct either their state and local income taxes or their sales taxes – whichever are higher.

Nationally, 35.1 percent of taxpayers itemized their deductions on their

2002 tax returns, and the number of Texans itemizing closely tracks that number, according to the Internal Revenue Service.

Those opting for sales tax deductions would choose between claiming a standard deduction or one based on actual receipts. Receipts for big-ticket items such as cars and boats could also be tacked onto a standard deduction.

The sales tax deduction was eliminated in the Tax Reform Act of 1986, and the new measure is expected to affect 55 million taxpayers nationwide.

Residents of Florida, Nevada, South Dakota, Tennessee, Texas, Washington and Wyoming would be most affected, as those states tax sales but not incomes.

Some lawmakers believe Alaskans would also stand to gain from the measure, but there are conflicting interpretations of the state's tax laws.

The measure is expected to save Texans $740 million, and Texas Comptroller Carole Keeton Strayhorn believes it will create $623 million in investments and $923 million in increased state gross product.