Why, state Sen. Leah Vukmir wondered, had Baldwin voted against the GOP tax overhaul that cut taxes for the middle class?
Without a hint of irritation at the ambush, Baldwin quickly flipped the question, pointing out middle-class relief would be temporary and blaming the tax changes for a northeastern Wisconsin paper company laying off 600 workers. Those workers don't care about the tax cuts, Baldwin said.
"Their company has rewarded them by saying they are going to close that plant," she said.
The episode was an example of the Democrat's reputation as a soft-spoken but tough political pro - a persona she's banking on to help her win a second term in a race seen as key for control of the U.S. Senate.
Derided by conservatives as the embodiment of the oft-ridiculed "Madison liberal," Baldwin is ramping up a campaign that plays up her work on moderate and core Wisconsin issues. Her first TV ads last week touted her buy-America plan that President Donald Trump supports and her work with Republican Sen. John McCain on lowering drug costs.
But she's also squarely on board with signature Democratic issues such as stronger gun control, universal health care and continuing a program that allowed children of immigrants here illegally to remain.
For Baldwin to win, she'll need people like Bob Brockway to vote for her. A 77-year-old retired truck driver living in Montello, Wisconsin, who calls himself an independent, Brockway voted for Baldwin in 2012, went for Trump in 2016, and intends to vote for Baldwin again this year.
Brockway got to know Baldwin several years ago as he met with her in Washington and in Wisconsin, seeking help with a fight to save truckers' pensions from deep cuts.
"She's down-to-earth people," Brockway said of Baldwin. "She don't act like she's a senator, she acts like a normal person, comes in and talks to everybody, listens to everybody's problem, tries to solve their problem."
Republicans accuse Baldwin of shape-shifting to downplay her liberal bent. They say she's out of step with voters in a conservative-leaning state on such issues as opposing the GOP's tax cut, and in her support for universal health care.
"That's the dichotomy she's got to deal with," said Mark Morgan, executive director of the Wisconsin Republican Party.
Baldwin, 56, is the Senate's first openly gay member, but she's never made fighting for gay rights a central part of her platform.
She was born in Madison and graduated high school as valedictorian before heading east to Smith College. She returned home to Wisconsin and two years later, at 24, won her first election to the county board. In 1992 she was elected to the state Assembly, one of only a handful of openly gay candidates nationwide that year.
She doesn't talk much about that on the campaign trail. But she does like to tell the story of how her grandparents, who raised her, could not buy health insurance for her because of a condition similar to spinal meningitis. Baldwin got better, but she invokes her personal experience often when explaining her support for the Affordable Care Act and universal health care.
Initially criticized as slow to respond to a whistleblower complaint over opioid prescriptions at a home for military veterans in Wisconsin, Baldwin has diluted the attacks by working with the family of Jason Simcakoski, a Marine veteran who died of an overdose there in 2014. She sponsored legislation in his name that now requires VA employees prescribing opioids to be better trained and to follow Centers for Disease Control and Prevention guidelines.
Money is already flowing against Baldwin. The Koch brothers and other conservative groups have spent more than twice as much against her than against all other Democratic Senate incumbents and candidates combined, $3.1 million to $1.4 million, according to the Center for Responsive Politics. One of her Republican challengers, Kevin Nicholson, has benefited from another $3.1 million spent on his behalf.
EMILY's List, the group that backs Democratic women who support abortion rights, is ready to push back. President Stephanie Schriock says the group is making Baldwin's re-election a top priority.
Baldwin has stockpiled money - $7 million at year's end - while Republicans are looking at a messy August primary between Vukmir, a longtime ally of Gov. Scott Walker, and Nicholson, a former Marine.
Baldwin's approval rating sat at just 37 percent in a Marquette University Law School poll released this week, with 39 percent disapproving, a sign her opponents said shows she's vulnerable.
But Democrats are optimistic after winning a special election in January for a state Senate seat that had been under Republican control for 17 years in a district Trump carried.
"Tammy has had a very successful career in getting elected to things that she wasn't supposed to get elected to," said U.S. Rep. Mark Pocan, a Democrat who has known Baldwin since they served on the local county board together in the early 1990s.
Brockway, the retired truck driver, said he tells other Trump supporters to give Baldwin a chance.
"I just tell them to listen to her when she's speaking. She tells it from the heart," Brockway said. "She does what's right for people. ... Some of these people in Washington, they don't hear us."
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