HARRISBURG — A radio ad playing on a Philadelphia station booms repeatedly with the notorious maxim "greed is good" and likens Republican Pat Toomey to Gordon Gekko, the fictional, high-flying, filthy-rich financier who made the mantra famous in the 1987 movie "Wall Street."

In a black-and-white TV ad, a deep-voiced narrator says President Barack Obama has overseen "the destruction of our health care," "record deficits" and "tragic unemployment" and calls Democrat Joe Sestak his accomplice.

The ads are part of a massive influx of campaign dollars — some of it from undisclosed donors — raised by Washington, D.C.-based groups that are trying to influence Pennsylvania's hotly contested U.S. Senate race between Toomey and Sestak.

The stakes are high, with the potential for the tight Toomey-Sestak contest to help decide partisan control of the U.S. Senate. The candidates are battling to succeed a fixture of Pennsylvania politics, five-term Sen. Arlen Specter, whom Sestak surprised in a May primary.

As Tuesday's election gets closer, the rate of spending is accelerating, leaving Pennsylvania residents disgusted and confused by TV ads that are predominantly negative.

"What are they looking to get in return?" questioned Jack Washenko, a 54-year-old registered Democrat smoking a cigarette on a downtown Scranton park bench Thursday. "What's in it for them? Like they say, you gotta spend money to make money."

Since the beginning of last week, more than $1 million a day has poured into the state for that race alone, with an average of one new TV ad appearing every day in October.

As of late Thursday, more than $23 million had been spent for things like TV commercials, fliers and Internet ads.

That makes Pennsylvania's race for U.S. Senate the nation's second-biggest draw of such outside money behind the Senate race in Colorado, according to the Sunlight Foundation, a Washington-based watchdog group that tracks campaign finance.

Combined with an equal amount of money spent by the Toomey and Sestak campaigns through mid-October, the price tag of the election is poised to pass $50 million.

In Pennsylvania, the biggest contributors of outside money are two key party organizations — the Democratic Senatorial Campaign Committee, at more than $8 million, and the National Republican Senatorial Committee, at more than $4 million — and a slew of groups driven by issues or ideology.