Trump-resistant and election battling Republicans including two former Presidents, two former Republican nominees, and several former 2016 presidential hopefuls are offering up excuses for why they will not attend the Republican National Convention in Cleveland next week, notably among them a break with a history of former Presidents attending their party’s convention.

Here are ten of the most prominent Republicans who say they’ll skip out on the convention and a few more who will or maybe won’t.

Two former Republican Presidents: George W. Bush and George H.W. Bush.

Presidents 41 and 43 announced in May that neither would endorse presumptive nominee Donald Trump, nor were either planning to attend the convention as reported in Politico.

In 2012 neither the 41st, nor 43rd former president spoke in person at the convention but did provide recorded messages. The Los Angeles Times offered a brief description of a video shown at that convention of the two former presidents Bush and their wives during which they praised one another and that year’s GOP presidential nominee Mitt Romney.

Former president George W. Bush may not have attended the 2008 convention in person, but he did stream in his speech via satellite. His address praised strongly the GOP nominee John McCain. The physical absence marked “the first president in a generation to miss his party’s nominating ceremony,” according to the New York Times.

In modern history almost all former presidents have participated in their party’s convention directly following their exit from office. Gerald R. Ford served as President from 1974 to 1977 and was the Republican Party’s 1976 nominee, but lost to Democrat Jimmy Carter. 1976 was the infamous contested Republican convention that put up Ford for the presidency over Ronald Reagan, who would become the party’s 1980 nominee and be elected President. Each of these, as well as former Presidents Bill Clinton and George H.W. Bush, attended the first convention for their party after leaving office, according to the Times. Presidents Lyndon B. Johnson and Richard M. Nixon were noted as exceptions to the tradition.

Two most recent Republican presidential nominees: 2008 failed nominee Sen. John McCain and unsuccessful 2012 nominee Mitt Romney also have expressed that they have no plans to attend this year’s RNC convention.

McCain has indicated that he will pass on the convention as he faces a tough re-election bid. McCain was tied in a recent poll with former Arizona State Senator Kelli Ward when the two were matched up head to head. McCain has also suffered in polls when matched against Democratic Party candidate Rep. Ann Kirkpatrick. Kirkpatrick pulled slightly ahead of McCain in an early June poll. Arizona’s primary election is August 30. Their presidential preference vote, which went hard for Trump, took place in March.

Romney, who has continually flirted with the idea of running again, lost the nomination to McCain in 2008, won the nomination in 2012, but ultimately lost the election to President Barack Obama’s bid for a second term. As Trump emerged as the increasingly likely nominee, Romney held a special event at the University of Utah in March. Drawing in attention with the lure of big news he blasted Trump and begged Republicans not to nominate Trump.

Sen. Bob Dole is the sole former Republican presidential nominee that has communicated he will attend this year’s nominating convention, an aide to Dole told CNN. Dole was the nominee in 1996 but lost the general election to Democrat Bill Clinton.

Four former presidential candidates: Ohio Gov. John Kasich, Florida Sen. Marco Rubio, former Florida Gov. Jeb Bush and South Carolina Sen. Lindsey Graham have expressed that they will abstain from the convention. Kasich has failed to honor an earlier pledge to support the Republican nominee as Trump emerged as the presumptive nominee. “It’s painful” was his response to endorsement questions during an appearance on MSNBC’s Morning Joe in June. “I’m not making any final decision yet, but at this point I just can’t do it.”

Kasich’s choice to dodge the convention in Cleveland piles on his opposition as it is being held in the very state of which he is governor.

Sen. Rubio’s spokesperson Olivia Perez-Cubas blamed Rubio’s absence on his late decision to jump into a re-election bid to retain his seat in the U.S. Senate. CNN reported her statement that the former 2016 presidential candidate previously planned to attend. Unlike Kasich, Rubio has indicated he will support the Republican nominee.

Then there’s the Bush that sought to be the third to serve as president. Jeb Bush rebuffed a recently dubbed presumptive nominee Trump with backhanded congratulations in May, writing in part, “In November, I will not vote for Donald Trump or Hillary Clinton…” Bush pledged, along with eight other candidates who took to an August debate stage, to support the Republican nominee. Trump later agreed to that pledge and re-affirmed it during a March debate.

Sen. Lindsey Graham, who only reluctantly supported Trump’s closest competitor Sen. Ted Cruz when all other viable options had fallen away, declared in May that he could not “in good conscience support Donald Trump” and would not attend the convention, according to TIME. Graham resigned from the race for the nomination in December with just 0.5 percent support. Less than a month later Graham endorsed establishment darling Jeb Bush.

In late May Graham appeared to be privately supportive of Trump in light of the alternative, Democratic presumptive nominee Hillary Clinton.

Hints of a breakdown in some of the candidates’ pledge to support the nominee were highlighted in a March CNN Town Hall where Trump, Cruz, and Kasich each expressed their reconsideration.

New Hampshire Sen. Kelly Ayotte has counted herself among those who will not attend the convention, citing her own tough re-election battle. In April Ayotte told CNN that her presence is “unlikely.”

Illinois Sen. Mark Kirk will also be home fighting for re-election, his campaign manager said in a statement last April according to the Chicago Tribune. Kirk did, however, affirm ahead of the Illinois primary that he would “certainly” support Trump as the nominee. In June Kirk reversed course on support for Trump, telling CNN that he “cannot and will not support” Trump and would write in CIA director David Petraeus in the fall. Petraeus has been at the center of discussion as comparisons are made between the prosecution against him for mishandling of classified information and the FBI investigation of former Secretary of State Hillary Clinton that found that she showed “gross negligence” in mishandling classified information.

Sen. Richard Burr expressed uncertainty as to whether he will attend in June, according to CNN. Sounding as it was not likely he said, “I’m more valuable outside of Cleveland than inside of Cleveland.” The North Carolina Republican is also facing re-election.

Former Louisiana Gov. Bobby Jindal, also a former 2016 candidate, will not be attending the convention but told CNN in early May that it has nothing to do with opposition to Trump. He has expressed his support for the presumptive nominee and simply didn’t see a reason for his presence at the convention.

Trump has asked former Republican presidential candidate Sen. Ted Cruz to speak at the convention and Cruz has accepted, even as he has yet to make good on his early election season promise to endorse the nominee. Presumptive nominee Trump is expected to officially secure the nomination at the Cleveland convention next week.

2008 Republican vice presidential candidate and former Alaska Gov. Sarah Palin, after a landmark 2008 convention speech, chose to forgo the 2012 convention where Romney presided as the nominee for President. As a strong and early Trump supporter, Palin is a likely speaker at next week’s convention.

Follow Michelle Moons on Twitter @MichelleDiana