An undeterred Jeb Bush vows 'I'm all in'

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CEDAR RAPIDS, Iowa—Of the two dynasty candidates in the 2016 presidential race, Jeb Bush has it much harder than Hillary Clinton. It's in the poll ratings, and the records.

The former Florida governor, once the presumed Republican front-runner, trails Donald Trump and Ben Carson nationally; Clinton leads the Democratic race despite her email troubles. More significant in the long run, while Clinton can point to the economic boom her husband presided over, Bush must defend the presidencies of his father and brother that both ended badly.

The candidate who vowed to run joyfully insists he's not soured by the campaign's challenging start.

Jeb Bush talks to John Harwood at the Parlor City Pub and Eatery in Cedar Rapids, IA.
Mary Stevens | CNBC

"Not at all," Bush said here over a blackened-chicken salad—ordered to suit the "Paleo diet" on which he has lost more than 25 pounds. Notwithstanding Trump's "low-energy" jibes, he said the diet has boosted his vigor, adding, "It's a great experience. I'm enjoying it a lot."

"In the long run, people are going to want someone that has the experience and the skills and the ideas to lift them up. I'm not deterred by that at all."

Complicating his effort are memories of the previous presidents Bush. His father, George H.W. Bush, lost his 1992 re-election as economic anxieties drove voters to independent Ross Perot and the eventual winner, Democrat Bill Clinton. His brother George W. Bush inherited a budget surplus from Clinton, cut taxes, then left office in 2009 amid a financial collapse and handed President Barack Obama a trillion-dollar budget deficit.

Now Jeb Bush is proposing a tax cut even larger than his brother's, one that would drop the top personal income tax rate to 28 percent, and the top corporate and capital gains rates to 20 percent. While critics warn of windfalls for the rich and swelling deficits, he insists it will spark both the economic growth and wage gains Americans have been yearning for.

"The corporate reform benefits everybody, all workers, because if you lower corporate rates, you're going to see an explosion of investment in their own country," he said. "We need to get to the 21st century industrial base. And I think a lower corporate tax rate will help get us there. "

And while top earners "do receive a benefit," he added, his plan overall would do "the opposite" of what critics claim.

"It provides tax relief for the middle class," he said. "Everybody freaks out about the deficit. And I worry about the structural deficit for sure. But if we grow our economy at a faster rate, the dynamic nature of tax policy will kick in."

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He shrugged off top-line data showing that the last two Democratic presidencies have overseen the addition of more jobs, and greater progress in deficit reduction, than the last three Republican ones including those of his family members as well as Ronald Reagan.

"You have to factor in that policies have long-term impacts," he explained, pointing to tax and budget deals under Reagan and his father. "The tax reform of the 1980s created an environment that President Clinton took advantage of. The PAYGO budget compromise, where there was an increase in taxes, but there was more importantly, a rule that every dollar of additional spending required a cut in spending, was very effective in restraining government during the Clinton era as well.

"Presidents and Congress have an impact particularly on tax policy to shape economic growth or the lack of it. The results can occur for a short period of time or a long period of time. The tech bubble created enormous economic activity. You think about all the capital gains revenue that came when people were selling stocks, and so then the crash created the opposite effect."

He refuted arguments that as Florida governor his own economic record was inflated by a real estate bubble that burst after he left office. "Eighty percent of the jobs created were not real estate related, and I left with $9 billion in reserves," he said. "We were triple-A bond-rated ... and we're still triple-A rated, because conservative leadership matters."

In defending his brother's economic record as president, Bush noted the impact of the 9/11 attacks as well as the burst tech bubble. But he faulted his brother and the Republican Congress for failing to restrain spending, including by expanding Medicare to cover prescription drugs without providing a source of financing.

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In addition to tax cuts, Bush proposes to streamline the federal regulatory process. He calls that necessary to speed needed infrastructure repairs for America's roads, bridges and ports. But he rejected calls from some members of both parties in Congress to provide additional financing for highways by raising the gas tax because "I'm not for raising taxes."

And despite an underwhelming performance so far, Bush vowed not to slow down now.

"It should be arduous—you're running for president of the United States, for cryin' out loud," he said with a smile. "I'm all in."