The Center for Responsive Politics estimates that by the time the last "soft-money" dollar has been counted, the amount contributed will be the greatest haul of its kind in the history of U.S. politics -- $3 billion for the federal elections alone. By the center's estimates 50 percent more dough has been contributed to campaigns this year than in the last presidential campaign season. We have companies like AT&T, Microsoft, Citigroup and Verizon Communications to thank for underwriting the blizzard of campaign propaganda.

The surging economy isn't the only reason that contributions are up. Since both the presidential race and control of the House are up in the air, many companies are betting that the wisest strategy is to prudently fund both sides of the aisle.

"There are no safe bets this year," says Larry Makinson, executive director of the center. "They've got to protect themselves by giving to both sides, and they're being shaken down mercilessly by fundraisers."

Not surprisingly, many of the biggest contributors are in highly regulated industries like telecommunications and finance.

Based on the latest available data from the Federal Election Commission, AT&T is the biggest single contributor to this year's election. As of Oct. 1, the telecommunications company -- a perennial major donor -- had given more than $4.3 million, with 62 percent of that money going to Republicans. AT&T has been lobbying Congress to change federal regulations that will force the telecommunications giant to sell some of its cable holdings. Verizon Communications and SBC Communications, two contenders for AT&T's telecom throne, are the fourth and seventh biggest donors, respectively.

Mergers are a huge reason for companies to give, give and give some more to members of the House and Senate. "You don't want any embarrassing hearing being called in Congress if you're trying to acquire a big company," says Makinson. While in the '70s many of today's brand of megamergers would have had members of Congress "pounding their fists," today's larger mergers are sailing by without so much as a peep.

Microsoft, still trying to recover from its antitrust hangover, is the second largest corporate donor -- having given more than $3.4 million at last count. Bill Gates and Co. seem to have learned their lesson from years of neglecting to remember political friends at election time. "I joke that what Microsoft is really after is legislation that makes it legal to give direct contributions to federal judges," says Makinson. The company has given almost evenly to Republican and Democratic forces this year.

Notably, many large unions, like the American Federation of State, County and Municipal Employees, the AFL-CIO and the Service Employees International Union, gave as much as the top corporate donors. But if business contributions and union contributions are taken in aggregate, the for-profit guys outspent the unions 15 to 1. Also, many of the top individual contributors are corporate CEOs who give their own money to a candidate in addition to what their corporation might donate. For example, Enron, a Texas energy company, is the 13th biggest corporate donor, and the biggest single donor, to George W. Bush over the course of his short political career. Kenneth Lay, CEO of Enron, had at last count also contributed more than $300,000 of his own money -- almost exclusively to Republican causes -- this year.

The moral of the story seems to be: Give, or take your chances. For many companies, opening up their ample wallets is undoubtedly intended not just for political favors but as a defense mechanism in case they should face some public relations debacle that congressional hearings wouldn't help. "That probably was Firestone's big problem," says Makinson. "They don't give enough campaign contributions. They give virtually nothing."

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