A key plank in Sander’s platform so far: a much expanded estate tax.

“Democrats for a long time have been very reluctant to talk about taxes,” said Brad Bannon, a Democratic strategist. President Ronald Reagan “created a political climate where any talk of a tax increase was deadly for Democrats.”

That thinking has changed. Late in 2017, Republicans passed legislation that lowered taxes for four in five Americans. But the overhaul was often portrayed as aiding corporate and wealthy taxpayers more than the middle class and ended up a political liability in the midterms. Democrats are now capitalizing on the unpopularity of the law for the 2020 campaigns.

Warren has encapsulated what is likely to become the new Democratic playbook: Rather than propose several social programs and gloss over how to pay for it, she is proposing a revenue-generating tax, building up public support for it and then announcing how she’ll spend it.

She introduced a $2.75 trillion wealth tax last month. On Monday, she announced a plan to use some of the funds for universal childcare. Based on her campaign’s numbers, she would still have about a little more than $2 trillion to allocate to other programs.

Democrats have vowed to repeal much of the GOP tax overhaul -- which slashed the corporate tax rate to 21 percent and reduced taxes for many individuals. Yet reverting to the 2017 status quo isn’t enough for this cycle.

“Any presidential candidate needs to have a bold tax plan,” Gabriel Zucman, an economist at the University of California-Berkeley who has advised Warren. After the tax overhaul “candidates need to explain how they would change the system.”

Sanders would expand the estate tax to apply to estates starting at $3.5 million, down from $11 million, as well as increase the rate of the tax. Freshman Representative Alexandria Ocasio-Cortez of New York, who is too young to seek the presidency herself, has floated the idea of raising the top tax bracket to 70 percent for incomes exceeding $10 million. The ideas have moved the needle on what Democratic primary voters expect to hear.

Polling data show that many voters have long supported increasing taxes on the rich. About 60 percent of voters have consistently said over the past decade that upper-income individuals pay too little, according to data from Gallup.

“The politicians are just now catching up with the voters,” said Democratic pollster Celinda Lake.