Donald Trump now wants those 'sore losers' who haven't endorsed him yet to be punished.

At a campaign appearance yesterday in Bangor, Maine, the presumptive Republican nominee railed against his former rivals who didn't hold up their end of the Republican National Committee's pledge to support the eventual GOP nominee.

'They broke their word and in my opinion they should never be allowed to run for public office again because what they did is disgraceful,' Trump told the crowd.

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Donald Trump called out those 'sore losers' who haven't endorsed him yet - as seven of his former rivals have yet to officially say that they're behind their party's presumptive nominee

HOLD-OUTS: Sen. Ted Cruz (left), former Florida Gov. Jeb Bush (center) and Wisconsin Gov. Scott Walker (right) all signed the pledge, but haven't endorsed the GOP nominee

Trump said had he lost he 'would have honored the pledge.'

'It's amazing what can happen when you lose, it's amazing what can happen when you lose,' Trump said, according to CNN.

WHO HASN'T ENDORSED DONALD TRUMP? Sen. Ted Cruz Gov. John Kasich Gov. Jeb Bush Gov. Scott Walker Gov. George Pataki Sen. Lindsey Graham Carly Fiorina Advertisement

Out of the 16 candidates who ran for president against Trump, nine have now publicly expressed support for Trump while another seven Republicans are holding out.

Most notably – Sen. Ted Cruz and Ohio Gov. John Kasich, the last two Republican rivals Trump faced off against in the primaries.

Neither Cruz nor Kasich have endorsed their party's presumptive nominee, as they both had expected a contested convention and then a delegate fight in Cleveland.

Instead, Trump neatly beat them both in the Indiana primary on May 3, with Cruz dropping out that night and then Kasich pulling out the day after.

Wisconsin Gov. Scott Walker, who was leading in the Iowa polls early on, but whose campaign never really got off the ground, is another endorsement hold-out who's expected to play a large role in the Republican Party for years to come.

Most recently Walker told a local Fox affiliate that he wasn't even sure if he would speak at the Republican National Convention.

'It all depends on what the parameters are,' Walker said on Monday. 'If I can talk about my concerns about Hillary Clinton, then I'll probably talk about that.'

Also missing from the Trump endorsement list – former Govs. Jeb Bush and George Pataki, who likely won't run for office again.

ENDORSED TRUMP Sen. Marco Rubio Dr. Ben Carson Gov. Chris Christie Sen. Rand Paul Gov. Bobby Jindal Gov. Rick Perry Gov. Jim Gilmore Sen. Rick Santorum Gov. Mike Huckabee Advertisement

Of all his rivals, Trump probably had the most acrimonious relationship with Bush, who he dubbed 'low energy' last summer, a label that stuck like glue to the former Florida governor throughout the campaign.

Now Bush says he won't even vote for him.

'In November, I will not vote for Donald Trump or Hillary Clinton, but I will support principled conservatives at the state and federal levels, just as I have done my entire life,' Bush wrote on his Facebook page.

Not only is Jeb Bush skipping the RNC, but his brother, former President George W. Bush, won't be in attendance and neither will their dad, former President George H.W. Bush.

In fact the only living Republican nominee who plans to attend is the 92-year-old Bob Dole, as Sen. John McCain and Gov. Mott Romney are also sitting out.

Pataki, the former New York governor, has not endorsed Trump yet, but seems more open to it, suggesting in late May that he needs to hear some 'thoughtful positions' out of the presumptive Republican nominee.

Former Hewlett-Packard CEO Carly Fiorina, who briefly became Ted Cruz's running mate, has preached party unity but has yet to utter Donald Trump's name when making this case

Ohio Gov. John Kasich (left), the last Republican standing in the primary race, has yet to endorse - along with former New York Gov. George Pataki (right), who did applaud a recent Donald Trump hire

'He has yet to articulate a very strong policy towards how he’s going to keep America safe and go after radical Islam,' Pataki added.

More recently the former New York governor tweeted in support of Trump hiring Maricelly Velez-Delgado, a former Pataki adviser who now serves as Trump's deputy press secretary for Hispanic media.

That hire was announced last week.

Carly Fiorina, the former Hewlett-Packard CEO who ran for president and then said she'd be Cruz's running mate, has also stayed mum on an endorsement of Trump, though she's been active on social media criticizing Clinton and the Supreme Court.

In late May she called for GOP unity against Clinton at a speech in Stanford, Connecticut, though wouldn't mention Trump's name.

As for whether this was an official endorsement, an email addressed to a former campaign aide went unreturned.

Rounding out the batch of no-thank-yous is Sen. Lindsey Graham, who as of two weeks ago said he still couldn't support the presumptive Republican nominee.

Graham said Trump was moving in the right direction by meeting with the National Rifle Association to talk about restricting firearms from people who are on terror watch lists.

Earlier this month, Sen. Lindsey Graham suggested Donald Trump's comments about a Mexican-American judge could provide an 'off-ramp' for those looking to un-endorse the party's nominee

However, the senator also suggested in early June that is Republican peers un-endorse The Donald over comments Trump made about Mexican-American judge Gonzalo Curiel.

'If anybody was looking for an off-ramp, this is probably it,' Graham said.

As for the nine rivals who are now on Trump's side, some of those endorsements have been ringing.

Former Texas Gov. Rick Perry said Trump will 'peel [Clinton's] skin off' during presidential debates, while volunteering himself for the role of vice president.

Both Gov. Chris Christie and Dr. Ben Carson stood alongside the candidate to officially endorse.

Other endorsements have been of the hold-your-nose variety.

Sen. Rand Paul said that he will 'honor the pledge,' when he was asked about supporting Trump in mid-May by Breitbart News.

Louisiana Gov. Bobby Jindal said he was backing Donald Trump – after calling him an 'egomaniacal madman' in the primary – because he was concerned that Clinton might appoint bad justices to the Supreme Court.

'Mr. Trump might not support a constitutionalist conservative focused on original intent and limits on the court's power,' Jindal wrote in an op-ed for the Wall Street Journal headlined 'I'm voting for Trump, warts and all.'

'He may be more likely to appoint Judge Judy,' the governor said.