(CNN) While many progressive Democrats are looking at squeezing taxes out of the rich, newly declared presidential candidate Kamala Harris is focused on a more traditional goal: tax relief for the middle class.

who officially announced her California's junior senator,who officially announced her 2020 presidential bid on Sunday, says the middle class has been ignored. So she wants to provide them -- along with lower-income working families -- a tax credit of up to $6,000 a year to help them keep up with living expenses, a tax gift worth $3 trillion over 10 years.

. Warren, who is exploring a run, last week unveiled a proposal to levy a Sens. Bernie Sanders and Elizabeth Warren, both potential 2020 candidates, and freshman Rep. Alexandria Ocasio-Cortez, have all laid out plans to dramatically hike taxes the ultra-wealthyWarren, who is exploring a run, last week unveiled a proposal to levy a wealth tax on those worth more than $50 million, while Ocasio-Cortez has suggested imposing a 70% tax on income above $10 million to pay for a "Green New Deal" that would include a jobs guarantee and investment in renewable energy.

Harris, on the other hand, is calling for directly making funds available to middle class and working Americans -- an approach that sounds less politically radical than her rivals' but is focused on addressing the immediate concerns of voters.

"They are mirror images of each other," said Howard Gleckman, senior fellow at the non-partisan Tax Policy Center. Harris' "focus is really on giving a big tax credit to low- and moderate-income people. She's focusing less on how she's going to pay for it. Warren is exactly the opposite. She's focusing mostly on taxing rich people and not saying very much yet on what she'd do with the money."

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