Thompson's spokeswoman Lisa Boothe issued a statement calling into question the integrity of the Marquette poll, saying it relied too heavily on respondents who identified themselves as Democrats.
That has been a frequent charge by Republican against Franklin's poll. He dismisses it, saying the poll represents a random sampling based on how people identify themselves. The results are not altered in any way to attempt to increase or decrease a political party's representation, he said.
Despite the poll's findings that Thompson is trailing, Boothe said he remained confident that his message was resonating with voters and he would prevail.
The poll also shows that the percentage of respondents who view Baldwin and Thompson favorably is the same — 38 percent — while Thompson's unfavorable rating is 51 percent compared with 45 percent for Baldwin.
"The advertising has done its damage to both candidates quite successfully," Franklin said. "But it leaves both candidates now in the position of suffering from negative views."
Nearly every ad run over a 30-day period ending Oct. 26 was negative, based on an analysis done by Kantar Media CMAG as reported by the Milwaukee Journal Sentinel. Of the 25,647 Senate ads aired in Wisconsin's television markets, 99 percent were negative, making the race the most negative in the country, based on the study.
While the ads may turn off some voters like Janka, it's galvanized others such as Baldwin supporter Marilyn Hetzler, 85, of Appleton.
"The commercials against her have been totally vicious," Hetzler said at a Baldwin campaign stop Tuesday in Appleton. "Tom has done nothing to stop them."
Thompson backer Barbara Malady, 62, of Waukesha said she voted for Thompson in part because she didn't like Baldwin's ads.
"I'm just not comfortable with Tammy," Malady said. "I don't like her commercials. I just don't trust her."
Associated Press writer Dinesh Ramde contributed to this report from Waukesha.