She has done this time and time again. Free college sounds great, but how would he get GOP governors to cooperate? Single-payer health care is popular with progressives, but how would he get Republicans in Congress to go along with it after the nasty Obamacare fight?
This is essentially the same position Clinton found herself in in 2008, when she ran against another guy with big ideas who argued the right person could change politics.
"I could stand up here and say, 'Let's just get everybody together, let's get unified. The sky will open. The light will come down. Celestial choirs will be singing. And everyone will know we should do the right thing and the world will be perfect,'" Clinton said at the time, in a dig at then-Sen. Barack Obama's campaign rhetoric. "Maybe I've just lived a little long, but I have no illusions about how hard this is going to be. You are not going to wave a magic wand and have the special interests disappear."
This isn't a fun position to be in. It's hard, after all, to inspire people when you're telling everyone why a popular proposal isn't practical. And Clinton, predictably, has been struggling to attract idealistic progressives -- especially young people -- who are fed up with the current system and want to see change.
But it's also a position that many women do find themselves in, especially in the workplace. They are the "no" women, as New York Magazine writer Ann Friedman has called them:
The "no" woman is the opposite of a "yes" man. She’s usually not an administrative assistant or junior employee — most often, she is part of the leadership team in the company or on a particular project. And whether it’s part of her official job description or not, she’s the person who’s there to say no. She provides a counterbalance to the creative visionary and a reality check after a brainstorming session. She finds herself continually speaking up to temper her colleagues’ expectations or modify their strategies, either because it's part of her job to control budgets and keep everyone within the bounds of the law, or because she is simply more rational than the freewheelin' "ideas men" she works with.
Rebecca Traister, also in New York Magazine, notes that this gender box extends outside the workplace as well -- "it’s why Mom is the disciplinarian and Dad is the fun guy."
"Here is a truth about America: No one likes a woman who yells loudly about revolution," she writes.
The Washington Post's Dana Milbank argues that if Clinton was proposing the ideas Sanders is -- and didn't put forward very specific ideas on how to pay for and implement them -- the media "would mock it as patently absurd."
"Men are the guys who want to go out and buy the motorcycle and women are the purse-string holders," said Jay Newton-Small, a Time Magazine journalist and author of Broad Influence: How Women Are Changing the Way America Works. "It’s a very traditional role we are putting women into by making them the one saying, 'no, we can’t do all these really fun things.'"
Clinton likely came to Washington with far more idealism than she now displays. But her experience with the political machine has worn her down -- particularly the bruising health care battle she had in the 1990s. In those days, Clinton was known as the liberal in her husband's White House and often pushed top officials to be more progressive.
And now, in her exchanges with Sanders, she often invokes her experiences to explain why single-payer is unrealistic.
"You know, before it was called Obamacare, it was called Hillarycare. And I took on the drug companies and I took on the insurance companies to try to get us universal health care coverage," she said in Thursday's debate.
These experiences and this pragmatism draw many of Clinton's supporters -- older women, in particular -- to her. At event after event in New Hampshire this month, Clinton backers said they related to the sexism and double standards that the former secretary of state has endured and admired her for fighting them.
"Being a woman, even as an assistant superintendent of schools, I used to be the only woman in the room. And now it's different. And that's because of women like Hillary Clinton who have made a difference," said Mary Health, 70, of Manchester.
"Nothing can be tougher than having your boss tell you you can't have the raise you deserve because the other guys are married and have kids," added Joni Salvas, 74, who was also volunteering at Clinton's Manchester office and had worked in manufacturing.
"Hillary has been through that too, absolutely. But not as bluntly as I have," she added. Salvas said she eventually left that field because "I don't have a military pension, I don't have a penis and I'm getting the hell out of this joint."
There are, of course, exceptions to these gender expectations. Sen. Elizabeth Warren (D-Mass.) is an example of a female politician who is known for championing big ideas and has been able to break the traditional stereotypes. And it's not surprising that many in the Democratic Party are disappointed that she didn't run for president this cycle.
But she is still not the norm. More often, female politicians are known less for their big ideas and more for being capable, competent and cooperative -- all important traits that Washington could use more of, but also far harder to sell when running for president.