OAKLAND, Calif. — The docks at the Port of Oakland are a tangle of cranes, shipping containers, railroad tracks and snaking lines of trucks waiting to load and unload cargo.

Streamlining this kind of traffic is one of the few ideas Donald J. Trump and Hillary Clinton agree on.

Mrs. Clinton has said that if she is elected president, her administration will seek to spend $250 billion over five years on repairing and improving the nation’s infrastructure — not just ports but roads, bridges, energy systems and high-speed broadband — and would put an additional $25 billion toward a national infrastructure bank to spur related business investments. Mr. Trump said he wanted to go even bigger, saying his administration would spend at least twice as much as Mrs. Clinton.

Mr. Trump, taking a page from liberal economists, said he would fund his plan by borrowing several hundred billion dollars, but has offered no specifics. Mrs. Clinton’s more detailed proposal, by contrast, would be paid for by a business tax overhaul aimed at collecting additional revenue from companies that have parked assets abroad.