Erica Sagrans is campaign manager of Ready for Warren. She worked for President Barack Obama's 2012 re-election campaign and the Working Families Party. Charles Lenchner is co-founder of Ready for Warren and is the director of Organizing 2.0, which trains progressives and labor organizers in digital communications. He is also a co-founder of People for Bernie. The views expressed are their own.

(CNN) Elizabeth Warren's rallying cry is simple: If we fight for our values, we will win. And the question she's asked supporters is this: Are you ready to fight?

It was that fearless, fighting spirit that inspired us to start Ready for Warren more than a year ago to draft Elizabeth Warren to run for president. We believe the movement to draft Warren fundamentally changed the terms of the 2016 debate, and these days, just about every Democrat running for president seems to sound a lot like Warren. Few people have ever played as large a role in a Democratic presidential primary without even entering the race.

But having demonstrated how much support Elizabeth Warren has, we've spent the past few weeks listening to our grassroots supporters and the progressive community about what they want to do next. And one thing we heard time and again is that they're ready to play a big role in 2016, fighting alongside Warren on issues like trade, student debt, and reining in Wall Street.

They are also ready to back "Warren Wing" candidates who embody Warren's fearless brand of progressive populism. And although it isn't just about the presidency, 56% of supporters have urged us to back Bernie Sanders as the candidate currently running for president who best embodies the values that Warren champions.

That's why on Friday, Ready for Warren is launching a new grassroots initiative called Ready to Fight -- and Ready to Fight is endorsing Bernie Sanders as its candidate for president.

Why?

Because while Warren is the champion who inspired this movement, the draft effort was never just about her -- it's about her message and the values she represents. Bernie Sanders has caught fire in a way that's reminiscent of the draft Warren movement itself -- from the Internet to town halls in Iowa, Sanders has captured the imagination and support of people looking for a real progressive challenger in the 2016 Democratic primary.

One reason we're witnessing such a surge of support for politicians like Sanders and Warren is that they have given voice to Americans' deeply-felt frustration that the game is rigged against working people and stacked in favor of corporations and the very wealthy. For example, Robert Reich, citing a Pew report, notes that "the percentage of Americans who believe most people who want to get ahead can do so through hard work has plummeted 14 points since 2000."

While it's harder and harder for working people to get ahead or even get by, their voices are being drowned out by corporate influence and a flood of money in politics -- some $3.7 billion in last year's election cycle alone

Indeed, a 2014 Princeton study of more than 1,800 policy initiatives concluded that , over the past two decades, the United States has transformed from a representative democracy to a country where the elites hold power and shape policy, regardless of the will of the majority of voters. We've seen this imbalance play out with the outsize influence of corporations in the fight over the Trans-Pacific Trade Partnership. About 500 corporate trade "advisers" have access and input into the details of the trade deal, while the text has been kept secret from representatives from labor and environmental groups, as well as the media and voters.

As the gap in priorities between policy makers in D.C. and people across America widens, the voices of progressive populists like Warren and Sanders are growing louder and louder. But to be successful, they need the power of the people behind them -- people who are willing to stand up and fight.

The launch of Ready to Fight doesn't mean the movement to draft Warren is over. Organizations don't create movements, and they can't end them. There is still a real and widespread desire to see Elizabeth Warren run for president, and Ready for Warren is continuing to organize in order to make the case to Warren, and the country, that she should be a candidate in the 2016 race. We're a long way from Iowa, and no one knows what the future holds.

But this effort has always been a bottom-up movement. It's an expression of a deep and broadly felt desire for leaders who are willing to stand up to powerful interests and fight for working families. The Warren Wing is on the rise -- you can see it in everything from the fight against TPP to the growing momentum around Bernie Sanders, and in the way Hillary Clinton and even Republican candidates are echoing Warren's themes on income inequality.

We're ready to fight -- standing with Elizabeth Warren and Bernie Sanders to make sure the values we share are represented in next year's presidential election.