Third party candidates rarely make much impact in US presidential elections – the system is too heavily loaded against them. However, in 1992 a maverick campaign by the billionaire businessman Ross Perot, who has died aged 89, gained 19% of the popular vote, costing President George HW Bush a second term in the White House and shifting President Bill Clinton’s political agenda.

By denouncing the persistent federal deficit and calling for a balanced budget, Perot attracted the largest popular vote ever recorded for an independent presidential candidate. His ability to appeal to one in five voters convinced Clinton that he would have to back away from the Democrats’ spending plans on which he had campaigned.

Within days of taking office Clinton ruled that reducing the deficit must become the overriding theme. Against vehement protests from his own White House team, Clinton abandoned his planned tax cuts for low earners and froze the entitlement programmes on which many of America’s poorest citizens depend.

Ross Perot, centre, with Bill Clinton, left, and George Bush Sr at the end of their presidential debate in Michigan in 1992. Photograph: Mark Cardwell/Reuters

It was a high-risk strategy that cost his party dearly in the 1994 midterm elections. When it had been triumphantly vindicated by the $122bn budget surplus amassed at the end of Clinton’s second term, Perot had, ironically, become no more than a footnote in American political history, scuppered by the quirky attributes that had brought his initial success.

Born in Texarkana, Texas, on the state border with Arkansas, Ross was the son of Gabriel Ross Perot, a cotton broker and part-time horse trader, and his wife, Lulu May, a secretary. He had a host of odd jobs, from breaking horses to selling newspaper advertising. At 19 he was urged by his father to enrol at the US Naval Academy, from which he was assigned as a junior officer, first to a destroyer and later to an aircraft carrier. His unruly temperament did not respond well to military service, as his letters home increasingly demonstrated, but he gritted his teeth and served out his commission (1953-57).

He then joined IBM as a salesman and, though his sharp business instinct brought him fast promotion, he again showed himself a square peg in the company’s round-hole culture. He resigned after a row about commission payments and, with $1,000 borrowed from his wife, Margot Birmingham, whom he had married in 1956, set up the company through which he made his fortune.

From 1962, with the world shifting from paper records, Electronic Data Systems (EDS) equipped itself to be able to take on the contract to computerise the files of the US government’s vast Medicare organisation, set up by President Lyndon Johnson in 1965 to provide healthcare for millions.

Perot never looked back. Having received federal funding to develop his Medicare software, he hung on to the copyright and then negotiated state-by-state contracts obliging local Medicare offices to pay royalties for its use. EDS’s profits rapidly soared to 30% a year.

In 1968, when he floated the company, its shares rose rapidly. A major business magazine commented that Perot had made the fastest fortune in Texas history. His vast new wealth and his company’s expanding government contracts attracted the attention of the Nixon administration in Washington (to which Perot later gave munificent financial support).

Ross Perot in 1968 at Electronic Data Systems. Photograph: AP

In 1969 the White House asked him to investigate the treatment of US prisoners of war in Vietnam. One unexpected outcome was Perot’s quixotic attempt to organise an airlift to North Vietnam of food and medical supplies for the prisoners.

It turned into a fiasco when the project met not only the predictable hostility from Hanoi and Moscow but from Washington as well. Perot remained obsessed with the PoW issue long after the Vietnam war had ended, and repeatedly accused successive administrations of failing to secure the return of every prisoner.

His generally explosive response to world events emerged again in 1978 when two EDS employees in Iran became embroiled in a contractual dispute with the Shah’s tottering regime. Charged with corruption, they were imprisoned and the company was told it would have to pay $12m to get them released. Perot decided that the Carter administration was too supine about the case. He organised a rescue mission commanded by Col Arthur Simons, a retired special forces officer, and with himself and other company employees as members.

In the chaos leading to the Shah’s flight into exile in early 1979 they could do little at first. Their opportunity came after four frustrating weeks when a revolutionary mob attacked Qasr prison in Tehran and released its 10,000 inmates. Perot and Simons eventually found their colleagues, bundled them into a van and, after a hair-raising journey out of the capital, bribed their way across the Turkish border. The episode inspired Ken Follett’s On Wings of Eagles and a television miniseries.

In 1984 Perot sold EDS to General Motors for $2.4bn, hanging on to enough shares to give him a seat on the GM board. Within two years, however, he was embroiled in a predictable row with his fellow directors and resigned, founding another data processing company, Perot Systems, in 1988.

His sideways eruption into the 1992 election campaign caught everyone by surprise. He announced on a radio show that he was prepared to run if his supporters got his name on the ballot in all 50 states – no small undertaking when each state has its own legal and financial hurdles.

Then he embarked on a campaign almost entirely concentrating on TV and radio, taking advantage of myriad free appearances on chat shows but also spending millions on what he dubbed “infomercials”. He was a natural performer, with a ready command of one-liners that drew high enough poll ratings to qualify him for a place in the televised presidential debates. In one of them, when Bush tried to downplay the budget deficit, Perot riposted that the hole in the national accounts was “like a crazy aunt you keep down in the basement”.

He also appealed to a burgeoning audience by comparing the creaking US tax system to “an old inner tube that’s been patched by every special interest in the country”. In the middle of the campaign, however, his erratic temperament took over and he withdrew his candidacy, prompting a barrage of hostile press comment about his past behaviour. Three months later, when his name was on every state ballot, he abruptly resumed his campaign, saying he was responding to “millions of phone calls”.

In the November poll he won a startling 19.74m of 104.43m popular votes – but did not secure a single electoral college vote. The idiosyncrasy of this constitutional lottery was heightened by comparison with the 1968 poll. Then George Wallace’s white supremacy campaign attracted half the support that Perot won, but gained 46 electoral college votes.

This 1992 result was the high point of Perot’s political career. In 1995 he attempted to formalise his beliefs by organising the Reform party, which he then used for a ferocious but futile assault on the North American Free Trade Area. The party, however, soon fell victim to his egocentricity and was quickly riven by factional disputes.

Though Perot ran against Clinton in 1996 his popular support was more than halved. He did not qualify for the nationally televised presidential debates and so made little impact on the electorate. His bid eventually attracted 8% of the popular vote but, with the Reform party fracturing around him, he was a spent electoral force.

The national debt continued to concern him, and in 2008 he launched a website to track the rising total. The following year he received a special award from the Veterans Affairs department in recognition of his support for military welfare causes.

He is survived by Margot, five children, 19 grandchildren and a sister.

• Henry Ross Perot, entrepreneur and political campaigner, born 27 June 1930; died 9 July 2019