Around the country today, protests will take place demanding a $15 minimum wage. That would more than double the current federal minimum of $7.25.

And guess what: A push for higher wages is beginning to look like a real movement, with all the possible political effects that entails.

Here in the nation’s capital, a new campaign is starting to put a measure on the ballot to raise the city’s minimum to $15, which would have Washington join Seattle and San Francisco, other cities that recently voted to raise their minimums to that level in stages over the next few years.

Regardless of the state of legislative action, companies are feeling pressure to increase wages. McDonald’s announced a wage increase at its company-owned stores, and though it was criticized because the increase was only $1 an hour, what may be most significant is that they felt the need to boost wages at all. Even the notoriously stingy Walmart recently said it would increase its own minimum wage to $9 an hour this year and $10 next year.

As a movement, this push confronts some real obstacles, despite the fact that about 70 percent of the public consistently tells pollsters they’d like to see the minimum wage increased. Congress is controlled by a party that is steadfastly opposed to increasing the minimum. Many middle-class workers don’t see the minimum wage directly affecting them. Organizing those who would most directly benefit is a difficult task. And perhaps most importantly, the natural foundation for such a campaign — labor unions — are at a place of historical weakness.

Despite all that, momentum for this movement seems to be building, in part because it has a very specific demand. It’s one thing to talk in general terms about income inequality and stagnant wages, but the advocates of the $15 minimum say, “Here’s something we can do about it right now. Which side are you on?”

The more attention it gets, the more Democratic politicians will need to take a stance on this, and it seems pretty obvious which position they’re most likely to take. It’s particularly important what Hillary Clinton does, since she is very close to being the de facto leader of the Democratic Party. As Noam Scheiber explains, the $15 campaign puts pressure on Clinton to come up with a number for what she would like the minimum wage to be. President Obama has proposed raising it to $10.10, which in the face of a campaign for $15 may sound too tentative.

That demonstrates how even without a dangerous primary opponent (yet anyway), Clinton can still be pulled to the left. The $15 campaign could well expand the terms of the debate, defining what real action (and not mushy compromise) would look like. The fact that increasing the minimum wage is so consistently popular gives Clinton room to make her position even more liberal.

For their part, Republicans are intimidated by the minimum wage issue — they don’t want to increase it, but they know how unpopular that position is. So they say things like “I don’t want people to make $10.10 an hour. I want them to make $30 an hour,” but without any new law; only through growing the economy (that would be Marco Rubio), which is a laughably transparent dodge. The more obvious it is that they’d rather talk about something else, the more likely Clinton is to press the issue.

The minimum wage is obviously not the only policy change we could make to address inequality. But it’s something everyone understands, and with a growing movement behind it — including what will likely be a series of ballot measures around the country in 2016 — it could become an important part of the debate in the presidential campaign.