Who fights for the middle class? Elizabeth Warren, Donald Trump trade barbs.

Sen. Elizabeth Warren has attacked Donald Trump in another sign, that although she's not in the race, her vote counts as a liberal who appeals to the same base that supports Trump – the discontented middle class.

First Look

Donald Trump and Sen. Elizabeth Warren (D) of Massachusetts entered another round of sparring Tuesday, a sign the battle for the hearts and minds of the middle class will continue into the general election. 

"Donald Trump was drooling over the idea of a housing meltdown because it meant he could buy up a bunch more property on the cheap," Senator Warren said Tuesday at the Center for Popular Democracy in Washington. "What kind of a man does that? Root for people to get thrown out on the street?"

She called Mr. Trump a "small, insecure moneygrubber," pointing to comments he made in 2007 about making more money in bad markets than in good. 

"Pocahontas is at it again," was Trump's response, in an email to the Associated Press. "She scammed the people of Massachusetts and got into institutions because she said she is Native American. She's one of the least successful Senators in the US Senate."

Trump has alluded several times to criticism from Warren's successful 2012 campaign against Sen. Scott Brown (R) that she misleadingly identified herself as a Native American on the Harvard Law School directory. The two have sparred throughout the presidential campaign, trading rhetoric of the left and right, as businessman Trump touts his financial credentials and liberal champion Warren criticizes Wall Street.

"Donald Trump is worried about helping poor little Wall Street? Let me find the world's smallest violin to play a sad, sad song," Warren said.

"I borrowed $1 million dollars and turned it into a great $10 billion dollar company in a relatively short period of time," Trump said. "If goofy Elizabeth Warren could do the same thing for the United States, which she can't, this country would be proud again."

Warren's success in appealing to the left has pushed Democratic candidate Hillary Clinton, who spent decades as a relatively centrist Democrat along with her husband, further into the liberal camp. Ms. Clinton's language now mirrors Warren's class-based tirades on Big Business, as the Monitor's Linda Feldmann noted early on in the bid for the Democratic nomination:

Clinton has also firmly planted a flag in cultural liberalism. In her announcement video, she included a gay couple planning their wedding, a lesbian couple, a biracial couple, and two Hispanic brothers speaking, in Spanish, about the business they’re starting. . . .

There are multiple reasons for Mrs. Clinton to hug the left. First, she needs Senator Warren’s supporters to get excited about her – and not just vote for her grudgingly in the general election. She needs them to donate and volunteer. If enough Warren enthusiasts sit this election out, Clinton could have a hard time winning.

This report contains material from the Associated Press.