Via the Washington Post. Now that the Elizabeth Warren wing of the party has cleared space for Democratic candidates to move left, I expect we will continue to see them do so:

So far, Clinton hasn't embraced the liberal prescription for Social Security, but her views could be changing. At a town hall here Tuesday, she said she'd be open to a Social Security tax increase proposed by Sen. Bernie Sanders (I-Vt.), her radical rival in the primary.

During the 2008 campaign, Clinton had flatly rejected such an increase. Her comments this week could suggest that she has warmed to the idea, or that she is responding to a broader shift to the left among Democrats.

Clinton was responding to a question from the audience at a community college about the fact that the wealthy and upper middle class don't pay Social Security taxes on anything they earn above a certain amount. That limit is $118,500 this year.

"I can understand why you'd think that was unfair," the former U.S. senator and secretary of state said, before suggesting an increase in the limit. If the cap were raised, anyone pulling down six figures this year would have to pay taxes not only on their first $118,500, but also on any money they made above that amount, up to the new limit.

Clinton then described an approach similar to Sanders's -- raising taxes only on the wealthiest earners to avoid an increase for people who consider themselves upper middle class.

"We do have to look at the cap, and we have to figure out whether we raise it or whether we raise it a little and then jump over and raise it more higher up," Clinton said.

Many liberal experts on Social Security argue for raising the limit on taxable earnings as a way to bring more money into the program, helping to ensure that benefits will be available for future generations of American retirees. Social Security's main trust fund will be exhausted around 2032, the Congressional Budget Office projects, at which point the system would no longer have the money to pay benefits in full.