At first glance, the Colorado Senate race may look like an instant replay from 1996, when the same two candidates squared off for a Senate seat. But a closer look shows that this time around, the race has been nothing short of a knock-down, drag-'em-out street brawl.

Political observers say Democratic candidate Tom Strickland threw the first punch in a race that turned nasty early on.

Strickland, in his second run against Republican Sen. Wayne Allard, and with only a two-point margin to fill, started with a television commercial linking the incumbent to corporate scandal.

"The Qwest scandal: 24,000 jobs gone. Retirement savings wiped out. A criminal probe. The nation's greediest company is Wayne Allard's biggest contributor," the ad says.

"We're the David running against the Goliath, a challenger running against an incumbent senator," Strickland said.

And seeing how corporate responsibility is being used in campaigns across the country, the Allard camp answered back by pointing to Strickland's days as a lobbyist for the now bankrupt telecom giant Global Crossing.

The senator's camp also decided to recycle the label "lawyer-lobbyist" that it pinned on Strickland in 1996, a strategy that in a neck-and-neck race was credited with giving the senator his 1996 win by a 5-percent margin.

"More revelations about Tom Strickland and the news isn't good," Allard's latest television commercial says. "Tom Strickland worked for an out-of-state company that wanted to build an incinerator in Denver."

"The fact is that if you don't respond to a negative attack, it changes polls," Allard said.

By nature, political campaigns can get ugly, but what makes Colorado's race unique is that the state has never seen two candidates with this much animosity or fuel.

"There's no question that they are beating themselves with the same stick," said Colorado College political science professor Robert Loevy.

Colorado is crucial in this election because it is considered a state that can be influenced, Loevy said.

"Colorado tends to swing with the national electorate," Loevy said. "In other words, if there's a Democratic sweep in 2002, Strickland should win. That's usually what happens in Colorado. If the party sweeps nationally, they'll sweep in Colorado."

That has the big guns considering coming to town to help.  President Bush is planning a campaign stop for Allard, and rumblings are that former President Clinton may show up for Strickland.

Fox News' Alicia Acuna contributed to this report.