Mr. Sanders would also eliminate dynasty trusts, which allow families to shelter colossal holdings from taxes as they pass from one generation to the next. His office estimated that the bill would raise at least $315 billion over 10 years.

Aside from his policy particulars, Mr. Sanders has been explicit in his broader aims to restrain a homegrown aristocracy that inherits entrenched power and money. In announcing his tax proposal, he quoted Teddy Roosevelt’s warning about the dangers of a small class of enormously wealthy individuals “whose chief object is to hold and increase their power,” and underscored the moral and political imperative to put some limits on dynastic wealth.



“It is a very dangerous and unjust situation where so few have so much and so many have so little,” Mr. Sanders said in an interview. “When 46 percent of all new income goes to the top 1 percent, who believes that that is right or that that is good for the economy?”

Ms. Warren and Ms. Ocasio-Cortez have expressed similar sentiments. Warning of a poisoned democracy, Ms. Warren said government had “become a tool for the wealthy and well-connected.” Ms. Ocasio-Cortez told an interviewer. “I do think that a system that allows billionaires to exist when there are parts of Alabama where people are still getting ringworm because they don’t have access to public health is wrong.”

What more moderate candidates are proposing

If such comments inspire supporters, they also reveal potential divisions among the rising crop of Democrats.

The left-leaning Ms. Ocasio-Cortez, Ms. Warren and Mr. Sanders are all viewed as less business-friendly than Ms. Gillibrand, Mr. Booker and Ms. Harris, who have not made taxes on the rich a centerpiece of their public pitches. In that sense the latter trio is following the example set by Hillary Clinton in the 2016 campaign and President Barack Obama before her, with comparatively establishment-minded thinking on progressive taxation.

Ms. Harris, for example, was asked at a Drake University town hall in Des Moines about the morality of multibillionaires in a society with so many poverty-stricken children; she responded by calling for more taxes on the top 1 percent. Yet the California Democrat’s language, approach and proposals have a distinctly different tone than, say, that of Mr. Sanders, and she has not focused her campaign so far on attacking the wealthy or warning about an oligarchy. Her tax bill offers credits up to $6,000 for families earning less than $100,000 a year, without providing many details of who would make up the difference.