Throughout most of his campaign, Joe Biden has sought to put forward a singular idea: I care.

On Tuesday, he extended that sentiment into a specific proposal — to provide hundreds of billions of dollars for the care of young and old Americans.

The proposal, which would cost $775 billion over 10 years, would provide universal preschool to 3- and 4-year-old children, fund the construction of new child-care facilities and offer tax credits and grants to help pay for care positions for the young and the elderly.

It would be funded in part by rolling back some tax breaks for real estate investors and by “taking steps to increase tax compliance for high-income earners,” according to the Biden campaign.

Biden cast his plan as a lifeline to middle class families, saying that even before the pandemic they were feeling squeezed by the need to provide care for their children and in some cases also their parents. These families, he said, are now even more desperate, as care has become increasingly difficult to find.

“Everything feels different,” said Biden, speaking for just over 20 minutes from the Colonial Early Education Program at Colwyck Center in New Castle, Del. “There is just that feeling, that sense, that you don’t know if everything is going to turn out okay. I’m here to say it can be and it will be.”

Biden said his plan would “build a critical part of the labor force and help us recover faster and stronger.”

Biden’s plan would also fund 150,000 community health-care workers, with many targeted to work in low-income and racially diverse areas. It would create an $8,000 tax credit to help low-income families pay for child care. And it would add funding for community colleges so they can provide child care for students.

The plan builds on earlier Biden proposals to create a $5,000 tax credit for “informal caregivers” and some Social Security credits for those who care for parents or relatives.

Since locking up the Democratic nomination, Biden has sought to contrast himself with President Trump in various ways, from competence to integrity. But in few areas has he been as pointed as his assertion that Trump does not care about ordinary Americans the way Biden does.

Trump and his supporters take issue with that, saying the president’s record on job creation and tax cuts has done far more to help ordinary people than Biden’s big-government plans ever could.

On Tuesday, the Trump campaign suggested Biden’s plans would threaten the country’s free enterprise system. Campaign spokesman Hogan Gidley said the caregiving plan was an attempt to “remake America with socialist policies.”

Biden estimated that Tuesday’s proposal would lead to 5 million additional jobs, including both new caregiving positions and jobs the campaign said Americans could pursue once they are free from caring for children or relatives.

The proposal is the third part of a larger economic “Build Back Better” plan that Biden has rolled out over the past few weeks. He proposed spending $700 billion on American products as part of an economic nationalism plan. He also unveiled a $2 trillion clean energy initiative to eliminate carbon pollution from power plants by 2035.

Biden was among the few candidates who didn’t offer a child care plan during the Democratic primary, and liberal activists have been pushing his team to propose one.

Wendoly Marte, director of Economic Justice with Community Change Action, said she detected Sen. Bernie Sanders’s (I-Vt.) influence in Biden’s proposal, particularly his focus on increasing pay for care workers by allowing them to unionize.

“Oftentimes child care and early learning is just presented from parents’ perspective,” Marte said. “We want a broader conversation” that includes workers.

Biden referred repeatedly to caregivers’ working conditions during Tuesday’s speech, saying his proposal was “about dignity and respect for working people” and pledging that “no one should have to work more than one job to make ends meet.”

He signaled he would again focus on caregivers on Wednesday, when he will participate in a virtual town hall with the Service Employees International Union. Lee Saunders, president of the American Federation of State, County and Municipal Employees, also praised Biden’s plan Tuesday, predicting it will ensure workers receive “the respect they deserve.”

Biden has previously called for raising the minimum wage to $15 an hour. He also called for higher pay for teachers, grocery store workers and health-care employees, saying that the coronavirus has laid bare the need to protect workers that previously went overlooked.

Marte said that her group is “still analyzing” the details of the plan but said that it appears to be a “good start.” In general, some critics have said Biden’s plans for funding his proposals are vague or impractical.

Over the past few weeks, Biden has floated the idea of the federal government helping Americans take care of their families, including their parents and children. He said his plan was mostly aimed at women and predicted broad support.

“Think of the millions of people out there, particularly women who are home taking care of daughters, taking care of their elderly parents, people who are there taking care of the young and the elderly with special needs. They should be paid,” he said during a fundraiser in June co-hosted by Sen. Kamala D. Harris (D-Calif.). “We can make sure that we have a civilian force that is able to take care of those people and get paid to do it.”

During an economic roundtable last month in Philadelphia, Biden spoke about workers having difficulty obtaining affordable child care during the pandemic and said the government should pay for it “for as long as this crisis exists.” And he touted the idea of hiring 100,000 people as contact tracers to curb the spread of the disease, promising they would earn “a decent wage” and would then form the basis for a new public health workforce.

In his economic proposals, Biden has offered his own life story as the reason he understands the middle class. On Tuesday he made a point of discussing how much help he needed caring for his two sons after his first wife and daughter died in a 1972 car accident.

“As many of you recall, I was a single parent,” Biden said Tuesday. “Even though I had a lot more support than people going through tough times today, it was hard.”

He contrasted his story, and his empathy, with how he believes Trump has approached the presidency. “Donald Trump fails the most important test to being American president: the duty to care for you, for all of us,” Biden said, referencing news stories that Trump has lost interest in focusing on solving the public health crisis caused by the coronavirus pandemic.

“For all his bluster about his expertise on the economy he’s unable to explain how will actually help working families hit the hardest,” Biden said. “You know, he’s quit on you. And he’s quit on this county.”