WASHINGTON — President Barack Obama is sending Congress a $4 trillion budget Monday that seeks to raise taxes on wealthier Americans and corporations and use the extra income to lift the fortunes of families who have felt squeezed during tough economic times.

He would also ease tight budget constraints imposed on the military and domestic programs back in 2011, and unveils new initiatives including an ambitious $478 billion public works program for highway, bridge and transit upgrades.

The administration said the budget represented a strategy to strengthen the middle class and help “hard-working families get ahead in a time of relentless economic and technological change.”

“This country’s better off than it was four years ago, but what we also know is that wages and incomes for middle class families are just now ticking up,” Obama said in an interview broadcast on Monday’s “Today Show” on NBC. “They haven’t been keeping pace over the last 30 years compared to, you know, corporate profits and what’s happening to folks in the very top.”

Even before the massive budget books landed on lawmakers’ desks, Republicans were on the attack, accusing the president of seeking to revert to tax-and-spend policies that will harm the economy while failing to do anything about the budget’s biggest problem — soaring spending on government benefit programs.

Obama’s fiscal blueprint, for the budget year that begins Oct. 1, proposes spending $4 trillion — $3.99 trillion before rounding — and projects revenues of $3.53 trillion.

That would leave a deficit of $474 billion. Obama’s budget plan never reaches balance over the next decade and projects the deficit would rise to $687 billion in 2025.

The administration contends that various spending cuts and tax increases would trim the deficits by about $1.8 trillion over the next decade, leaving the red ink at manageable levels.