(CNN) Presidential candidates make promises. Often, they go unfulfilled by the winner.

Sometimes a divided Congress is to blame. Once in the White House, priorities can change. Lobbyists and activists intervene. Candidates lie to grease their paths to high office.

Usually though, these failures to follow through on campaign pledges come after the official wins and takes office.

Not so for Donald Trump. The Republican nominee has repeatedly defied his own commitments and fudged assurances -- and done it well before a single vote was cast.

Here is a short list of guarantees the Trump has either reversed on or refused to deliver.

1. Make public his tax returns

Trump is the only candidate in the modern era to keep his tax returns under wrap. The campaign in recent months has repeatedly attributed the decision to what it describes as an ongoing audit.

But it wasn't always this way. Opponents have been calling on Trump to reveal the records since the early rounds of the GOP primary contest. And Trump has often expressed his willingness to do just that.

Signing my tax return.... pic.twitter.com/XJfXeaORbU — Donald J. Trump (@realDonaldTrump) October 15, 2015

Asked by conservative radio host Hugh Hewitt in February 2015, a few months before the billionaire announced his candidacy, Trump said : "I would release tax returns."

How far back, Hewitt asked. "Three years, five years?"

"We'll take a good, strong look at that," Trump answered after some prodding. "But I have no objection to certainly showing tax returns."

By early 2016, though, Trump had gone back and forth on the issue. He had also become the front-runner for the GOP nomination.

In an interview on NBC's "Meet the Press" in January, he was questioned again. And again, he promised to make the paperwork public.

"We're working on that now," he said. "I have big returns, as you know, and I have everything all approved and very beautiful and we'll be working that over in the next period of time."

Trump hinted again in May that some kind of release could be in the works, telling Fox News, "I'll release. Hopefully before the election, I'll release."

Now, with 54 days until the polls open across the country -- and with Trump's son, Donald Jr., saying on Thursday the decision to withhold the returns is rooted in political concerns -- that seems unlikely.

2. Release 'detailed medical records'

Trump has repeatedly called out Democratic rival Hillary Clinton for a lack of "stamina," occasionally hinting at conspiracy theories that suggest his opponent is concealing a terminal or debilitating illness.

But even as Clinton has been faced with heavy criticism for a lack of transparency on this and other questions, Trump has offered less -- while promising more.

"I think that both candidates, Crooked Hillary and myself, should release detailed medical records," he tweeted late last month. "I have no problem in doing so! Hillary?"

I think that both candidates, Crooked Hillary and myself, should release detailed medical records. I have no problem in doing so! Hillary? — Donald J. Trump (@realDonaldTrump) August 28, 2016

Trump this week went a step further than he has in the past, releasing a brief letter from his doctor on Thursday that said he is in "excellent health." But that hardly amounts to "detailed medical records."

3. Hold a news conference on Melania immigration questions

Trump and wife Melania, a naturalized US citizen who was born in Slovenia, have repeatedly asserted that she "followed the law" as an immigrant.

When a series of reports surfaced this summer suggesting that her road had been more complicated, Trump -- who was mired in a series of damaging controversies at the time -- pledged to hold a news conference to quiet the doubters.

Trump spox Hope Hicks confirms @MELANIATRUMP will hold news conference on immigration questions. No timing details https://t.co/qGqDIbHRQf — Jeremy Diamond (@JDiamond1) August 9, 2016

On August 9, Trump told reporters the event would happen "over the next couple of weeks." More than a month later, we're still waiting.

4. Forswear the use of teleprompters

In the early days of his campaign, as he mocked shell-shocked Republicans (and Clinton), Trump often equated the use of teleprompters with weakness or incompetence.

"I say we should outlaw teleprompters for anybody, right? For anybody! For anybody running for president," he said to cheers in Iowa last summer.

By 2016, though, Trump had changed his tune -- and not just when he was giving tamer speeches with the help of his own teleprompter.

"I like using them on occasion, too, by the way. It's not so bad," he told supporters during a June event. "I've been given good reviews when I use crazy teleprompters, can you believe it?"

5. Use his own money to finance campaign

The Trump campaign, at least in the beginning, was boosted by two fundamental guarantees.

First, that he would deport undocumented immigrants while preventing new entrants by building a wall on the US-Mexico border. The other: that he, alone among the candidates, could not be bought or influenced by donors because he was financing his own bid.

"I don't need anybody's money," Trump said, announcing his run. "It's nice. I don't need anybody's money. I'm using my own money. I'm not using the lobbyists. I'm not using donors. I don't care. I'm really rich."

But a review near the end of the primary season found that roughly a quarter of Trump's campaign cash had come from individual donations. The billionaire had loaned the operation money -- and would subsequently forgive those debts -- so he came close, but his pledge to eschew donors ultimately failed.

As for the general election race, Trump was clear in the spring he would embrace more traditional fundraising methods if became the standard-bearer. He has delivered on that front. Working with the Republican Party, the campaign banked $80 million in July alone.

On a related note: Earlier in the campaign, Trump's pledge to donate $1 million to a military veterans' charity, raised during an event organized in lieu of attending an early primary debate, came into question when, months later, he had still not delivered the cash.

6. Pay legal fees for rally-goer who punched a protester

Warned by security that he could be the target of, as he put it, "somebody with tomatoes" at an Iowa rally earlier this year, Trump first asked supporters to "knock the crap out of" any potential hurlers, then added: "I promise you, I will pay for the legal fees. I promise, I promise."

In March, after a 78-year-old man was charged with assault after sucker-punching an African-American protester at a North Carolina rally, Trump doubled down.

"I've actually instructed my people to look into (paying the legal fees of supporters)," he told NBC.

Trump would back off the claim, and the offer, in subsequent interviews. He has not provided financial support to supporters in legal trouble -- possibly because his initial comments could help make a case that his campaign should be held liable for the violence

7. Make you tired of winning so much

Here's Trump on what his campaign would do and the effect his potential presidency would have on Americans:

"We're going to win so much, you're going to get tired of winning," he said in South Carolina before the February primary. "You're going to say, 'Please Mr. President, I have a headache. Please, don't win so much. This is getting terrible.' And I'm going to say, 'No, we have to make America great again.' You're gonna say, 'Please.' I said, 'Nope, nope. We're gonna keep winning.'"

Verdict? To be determined.