At last night's Republican debate in Milwaukee, the first question candidates got was something that hasn't come up yet in these presidential gabfests: whether any of them would support a higher minimum wage.

Predictably, they said no. "Wages too high," Donald Trump proclaimed, arguing that they made the U.S. noncompetitive. Ben Carson echoed him, saying high minimum wages just create unemployment, particularly for young people and African Americans. "If you lower those wages, that comes down."

Putting aside the economic merits of that argument, which has been extensively discussed in other fora, it's worth considering where that question came from: the masses of protesters outside waving signs for a $15-an-hour minimum wage. A year out from Election Day 2016, the union-backed Fight for $15 organization had staged protests all over the country, trying to send a message that low-income people who may have never voted before will get behind candidates who support boosting the minimum wage, along with priorities such as immigration reform and affordable child care.

It's very difficult to meaningfully sway election results with some street protests. But even getting candidates to talk about your issues, and make statements that you can either campaign against or hold them to down the line, counts as success.

The Fight for $15 is certainly addressing an obvious problem. Younger and less-educated people have consistently had lower election turnout rates than older, more-educated people (two traits that correlate strongly with higher incomes). That means they have less clout with politicians, who are then less likely to do things they want, like raise the minimum wage.

Actually getting them to the polls, however, is a tricky thing — especially when you're running a broad issue campaign, rather than one focused on a specific candidate. "I’m dubious that it will get translated into electoral politics," says Jan Leighley, a professor of government at American University who studies voter participation. "Getting media coverage might be a nice local angle in the context of a statewide race, but I find it hard to believe it can be sustained throughout the season."

Voter participation typically responds to large structural forces, as well as the traits of the individual candidate. Research on political activism among African Americans shows that participation rises with the involvement of black elected officials but sinks when people are in economic distress. And now, eight years of news about partisan bickering and gridlock have soured many young voters on politics generally, turning them toward direct pressure on corporations, technological solutions and "social entrepreneurship" as more productive avenues for making change.

But whether or not they make it out to the polls next November, it's likely that they've already had some influence.

You can see this effect in the Democratic presidential field: Although Hillary Clinton didn't commit to raising the minimum wage to $15, she did settle on $12. Her rivals, Bernie Sanders and Martin O'Malley, have endorsed the higher number, as has the Democratic National Committee.

The Fight for $15's influence is also evident, however, in statements by business interests who are dead set against it.

Take the Employment Policies Institute, which is closely aligned with the restaurant industry. It commissioned a survey of hundreds of economists and found that three out of four said a $15 minimum wage would cost jobs. That's actually not bad for a proposition that a few years ago might have been laughed out of any room full of economists. And on the question of whether the minimum wage should be raised at all from its current level of $7.25, 60 percent agreed that it should.

Also Tuesday, the International Franchise Association put out a press release condemning the protests — by arguing that there are better ways to address inequality, which isn't something business interests typically acknowledge is even a problem. "There is no question we should be looking at solutions to address the growing economic divide in America," said IFA chief executive Robert Cresanti.

That's how the Fight for $15 has operated: by drawing the debate toward its agenda, and expanding the range of policy outcomes that reasonable people discuss, rather than trying to get people excited about a particular candidate's platform.

"I think they’re going to be effective by pushing from the outside, pulling elected officials way further than they wanted to go," says Mary Kay Henry, president of the Service Employees International Union, which has bankrolled the campaign.

Trump and Carson even gave their campaign a new rallying cry. After the issue came up in last night's debate, the Fight for $15 sent out a text message to supporters: "BREAKING: Donald Trump just said: 'Wages are too high.' #Fightfor15 response: See you in Nov 2016."