"Talent is this year's No. 1 senator to get funding from five big agricultural corporations that have ties to hiring illegal immigrants," McCaskill told local reporters last week.

Both candidates oppose the immigration reform bill passed by the Senate in May, but McCaskill questioned Talent's commitment to cracking down on employers who hire illegal immigrants.

"The law is not only not being enforced by these [agricultural] employers," she said. "It is being ignored."

According to the Federal Election Commission's most recent fundraising data, which show money raised through March 31, Talent's more than $226,000 in agriculture contributions includes $6,000 from a political action committee representing Tyson Foods and $7,000 from a PAC representing ConAgra, a top food producer whose brands include Chef Boyardee, HealthyChoice, and Butterball. A PAC founded by agriculture giant Cargill, whose subsidiaries include a leading U.S. meatpacking company, chipped in an additional $6,000.

Such industries have been hot targets of immigration worksite crackdowns in the past. A 1999 INS enforcement effort called Operation Vanguard found that 19 percent of the workers in 40 meatpacking plants sprinkled across Nebraska, Iowa, and South Dakota— a total of 4,495 workers— had dubious immigration documents. A 36-count federal indictment issued in 2001 charged Tyson with knowingly hiring illegal aliens and conspiring with smugglers to bring them into the country. Although three company employees pleaded guilty and audiotapes featured a plant manager soliciting false documents, Tyson was ultimately acquitted.

Still, McCaskill's tactics are bold in an agricultural state. According to U.S. Department of Agriculture statistics for 2002, the most recent figures available, almost 68 percent of the land in Missouri is farmland.

Talent's spokesman Rich Chrismer says McCaskill's campaign also solicited donations from the Tyson PAC earlier in the race. Adrianne Marsh, a spokeswoman for McCaskill, says the agriculture giant received a "blanket fax sent out to a number of organizations" to publicize a campaign event near Kansas City. –Angie C. Marek