Donald Trump vows to spend twice as much as Hillary Clinton to fix America's roads, bridges and internet capacity.

"Nobody can build better than I can. Nobody knows construction better," Trump said Tuesday in an interview with Fox Business.

This isn't the first time Trump has promised he'll repair America's infrastructure, but now he's putting a dollar figure on just how much he thinks is needed.

Clinton's plan is for $275 billion to be spent over five years, a plan that experts across the political spectrum call her best economic idea, which will be a huge boost to the economy. Trump says he will do "at least double" that.

"You're going to really need more than [Clinton's plan]," Trump said on Tuesday. "We have bridges that are falling down."

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"The one thing we know about infrastructure spending is it's going to happen," says economist Peter Morici of the University of Maryland. "It's one of the few things Hillary promises to do within the first 90 days. Now Trump is saying he wants to do it."

There's bipartisan agreement to act. The debate now between Republicans and Democrats is how to pay for it.

Clinton has said she would raise taxes on businesses to fund more spending and she would also start an "infrastructure bank." That's basically a public-private partnership where the government puts in some money and private investors put in the rest.

So far, Trump is vague on the specifics.

"We have to fix our infrastructure. But we have to fix it without cost overruns," Trump said this week. He proposes "infrastructure bonds" that "people and investors" would buy. He also mentioned setting up an infrastructure fund, which sounds a lot like Clinton's idea.

"Like a lot of things Trump says, it's thin on details," says Morici, who points out the Chinese would basically be financing U.S. road repairs if Trump issued bonds.

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Overall, the response has been very positive to Trump thinking big on infrastructure.

"I think it's a great idea," says economist Mark Zandi of Moody's Analytics.

Zandi authored a report that concluded that over 3 million jobs would be lost if Trump pursued all the initiatives he has proposed. In contrast, Zandi found that Clinton's plans would create 10 million jobs.

Trump's latest proposal is a step in the right direction, Zandi says, but he's not ready to revise the stats for Trump-onomics until he sees more details.

"Trump has to scale back his tax cuts or figure out a way to pay for them," says Zandi. Trump's large tax cuts for businesses and individuals would add almost $10 trillion to the debt in the next decade -- about the same amount that President Obama has added in his term.

Now Trump would seemingly pile on more debt to finance road and bridge repairs.