Like Thompson, she has spent most of her adult life in public office, in her case since being elected to a county board when she was 24. If elected, Baldwin would become the first openly gay U.S. senator, though her orientation hasn't been an issue in the campaign.
Jean Lynner, a Republican voter from Waukesha, said she's not keen on anyone as liberal as Baldwin, who supported President Barack Obama's health reform plan and federal stimulus program. But she also has problems with Thompson, who she described as "an old politician" from an era of "good ol' boys clubs and backroom deals."
Thompson hopes to gain momentum on the campaign trail. He works crowds enthusiastically and thanks people by name in folksy style that quickly gets them smiling.
At a recent stop at Busch Precision in Milwaukee, Thompson spun stories about conversations he had with the company's founder more than 20 years ago and dropped names of people in the crowd.
"I'm not going to retire," he said, motioning toward the crowd. "Our best days are in front of us, Audrey."
Baldwin outspent Thompson on television advertising 3 to 1 in the race's initial weeks, helping to fuel her surge, but Thompson has raised $2.2 million since the primary, and benefited from millions spent by outside groups including Karl Rove's Crossroads GPS. That group put another $1.2 million into television ads on Wednesday, bringing its total to $5 million.
Both sides are now saturating Wisconsin media. About $19 million has been invested by outside groups alone in the race, second only to the sum spent on Virginia's Senate race, according to the Center for Responsive Politics.
Pro-Thompson forces hope there's still more liberal phobia in the electorate to mine. Their ads hammer Baldwin as to the left of both Obama and former House Speaker Nancy Pelosi -- "too extreme for Wisconsin."
The pro-Baldwin side counters by portraying Thompson as one of the detached elite __ "not for Wisconsin any more" since he made millions in the private sector in Washington after leaving government in 2005.
Even though polls indicate Wisconsin voters are nearly evenly split between Obama and Romney in the presidential campaign, they could wind up choosing candidates in other races with seemingly contradictory views, said McCabe. "This is a very schizophrenic state politically and always has been."
Associated Press writer Dinesh Ramde in Milwaukee contributed to this story.
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