Congress has to pass a budget by roughly December 13. Republicans want to cut Social Security benefits; Democrats want to cut benefits as long as they can also raise taxes on the wealthy. Sen. Elizabeth Warren doesn't want to do any of that. In a floor speech Monday afternoon, she insisted that the federal government could increase benefits.

"Today, Social Security has a $2.7 trillion surplus," the Massachusetts Democrat argued. "If we do nothing, Social Security will be safe for the next 20 years and even after that will continue to pay most benefits. With some modest adjustments, we can keep the system solvent for many more years — and could even increase benefits."

Warren insists that there is a retirement crisis, and that cutting benefits is not the way to fix it. She called out Democrats (including President Obama) who support "chained CPI" — a less generous way of calculating cost-of-living adjustments to Social Security benefits: 

Supporters of the chained CPI say that it’s a more accurate way of measuring cost of living increases for seniors. That statement is simply not true. Chained CPI falls short of the actual increases in costs that seniors face, pure and simple. Chained CPI? It’s just a fancy way of saying cut benefits. 

This speech shows the increasing divide in the Democratic party over economic issues — one that Warren is happy to call attention to, apparently. In the 2016 fantasy, Warren is the populist progressive in favor of financial regulation and social programs, while Hillary Clinton is the center-left liberal sitting in the pocket of big Wall Street donors. 

The likelihood that Congress agrees to expand Social Security before December is zero, but Warren's attack means that it will continue to be an issue in the Democratic Party in the coming years. Greg Sargent at The Washington Post writes, Warren's "popularity with the Democratic grass roots suggests that they will want to see these issues addressed no matter who enters the 2016 Democratic field." 

Warren is ready to have the "Democratic values" conversation. She closed her speech like this:

The conversation about retirement and Social Security benefits is not just a conversation about math. At its core, this is a conversation about our values. It is a conversation about who we are as a country and who we are as a people. I believe we honor our promises, we make good on a system that millions of people paid into faithfully throughout their working years, and we support the right of every person to retire with dignity.