[U.S. Senator] Elizabeth Warren is emerging as a kind of spokeswoman for the new economic populism that many Democratic activists want the party to embrace heading into 2014 and 2016. [A] speech that Warren [delivered] on the floor of the Senate suggests [that] the push to expand Social Security could become a key issue in the argument over the Democratic Party of the future. She strongly endorsed the push to boost Social Security benefits - in keeping with Senator Tom Harkin's proposal to do the same: Social Security isn't the answer to all of our retirement problems. We need to find ways to tackle the financial squeeze that is crushing our families. We need to help families start saving again. We need to make sure that more workers have access to better pensions. The absolute last thing we should be doing is talking about cutting back on Social Security. The absolute last thing we should do in 2013 - at the very moment that Social Security has become the principal lifeline for millions of our seniors - is allow the program to begin to be dismantled inch by inch. Right now, more people than ever are on the edge of financial disaster once they retire - and the numbers continue to get worse. That is why we should be talking about expanding Social Security benefits - not cutting them. Senator Harkin from Iowa, Senator Begich from Alaska, Senator Sanders from Vermont, and others have been pushing hard in that direction. Social Security is incredibly effective, it is incredibly popular, and the calls for strengthening it are growing louder every day."