The billionaire faced attacks by Ed Miliband before the election campaign over his sportswear firm's use of zero-hour contracts.
Scottish Labour leader Jim Murphy even protested outside a Sports Direct store last month in anger at the 700,000 people across Britain without guaranteed hours.
But Labour's pledge to ban the 'Victorian' deals became a distant memory after the Tories won a Commons majority.
That has secured the fortunes of the high street name, pushing Sports Direct shares up from £6.20 to £6.56 between Thursday afternoon and Friday morning.
Ashley, who the Sunday Times Rich List says is Britain's 22nd-richest man with a £3.5bn fortune, was widely reported to own a 55% stake in the clothing firm in January.
That would mean the value of his shares leaped from £2.04bn at 3.30pm on Thursday to £2.15bn at 9am on Friday.
Experts say Sport Direct's 5% shares surge was also helped by a £44m sale of offices in London's West End.
But they're still well short of the £9.22-a-share high they achieved in April last year.
Sports Direct settled a legal case over its use of zero-hour contracts in October after the firm was sued ex-employee Zahera Gabriel-Abraham.
Despite denying liability the firm made changes to its employment practices after she said: "I was told that if I took holidays, I wouldn't get holiday pay, and that if I was ill I wouldn't get sick pay.
"It made me feel trapped and helpless."
Her solicitor Elizabeth George added: "Zero hours workers are not second class workers. They have the right to be treated fairly and with respect."
Sports Direct is widely reported to have 20,000 workers on the contracts.
Ed Miliband said in his attack in November: "Sports Direct has predictable turnover, it is a modern company with stores on many high streets and, judging by its success, where many people shop.
"But for too many of its employees, Sports Direct is a bad place to work.
"This is not about exceptional use of zero-hours contracts for short term or seasonal work which some employers and workers may find convenient. This is the way Sports Direct employs the vast majority of its workforce.
"These Victorian practices have no place in the 21st Century."
Sports Direct did not comment on Mr Miliband's attack, but highlighted their statement at the time of the legal case setting out the changes they were making.
A spokesman said: "It was clear from the proceedings that we and Ms Gabriel-Abraham felt equally strongly about our respective positions and that each had different perceptions of the events that took place.
"The company will continue the process of reviewing, updating and improving our core employment documents and procedures across our entire business beyond its existing compliant framework."