Washington (CNN) Even by the colorful standards of presidential primaries, the 2016 election cycle has been filled with jaw-dropping, head-scratching moments.

And though the Summer of Trump -- featuring brawls over immigration, John McCain's war-hero status, Megyn Kelly's debate moderating skills and more -- is dominating the campaign trail now, the presidential election season was surreal from the start -- with the possibility of another Bush vs. Clinton matchup -- and has already provided a host of standout assertions, attacks and missteps.

Here are a baker's dozen of the most eye-popping moments so far:

1. Donald Trump says Megyn Kelly has "blood coming out of her -- wherever." And then he insists that "only a sick person" would think it was about menstruation.

Donald Trump wasn't pleased with the question Fox News host Megyn Kelly asked about his history of attacks on women during the first GOP presidential debate. So he attacked -- first on Twitter, and then in a Friday night interview on CNN during which he said Kelly had "blood coming out of her eyes; blood coming out of her -- wherever."

Was it a reference to menstruation? Most of Trump's Republican opponents thought so, and hit him for it. But Trump, standing firm in an extraordinary Sunday morning interview with CNN's Jake Tapper, said that "only a sick person" would make that assumption. "Do you think I'd make a stupid statement like that?" he said.

2. Hillary Clinton says she and Bill Clinton were "dead broke" in 2001.

JUST WATCHED The Clintons clean up 'dead broke' Replay More Videos ... MUST WATCH The Clintons clean up 'dead broke' 02:28

Still 10 months from launching her presidential campaign, Hillary Clinton raised eyebrows during a book tour by declaring that her family left the White House "not only dead broke but in debt."

The debt was the result of the legal expenses the Clintons had racked up, and the former secretary of state was attempting to explain the exorbitant speaking fees she's commanded since then. But she ignored another reality: The Clintons had the capacity then to quickly earn money in a way most Americans can only dream of. As she campaigns on a platform of middle-class economics, the remark could return in anti-Clinton ads.

3. Mike Huckabee says President Barack Obama is marching Israelis "to the door of the oven."

In an interview with Breitbart News, former Arkansas Gov. Mike Huckabee put his opposition to the Iran deal in the starkest terms possible , saying that President Barack Obama is on the verge of causing another Holocaust. "It is so naive that he would trust the Iranians. By doing so, he will take the Israelis and march them to the door of the oven," Huckabee said.

In a race where his presence has otherwise been low-key, the remark made Huckabee the center of attention for a few days, leading even some opponents of Obama's Iran nuclear pitch to say the presidential candidate went too far.

4. Ted Cruz calls Mitch McConnell a liar on the Senate floor.

Since his 2012 election, Sen. Ted Cruz of Texas has taken pride in his willingness to fight longer and harder than other conservatives -- even when that means the government shuts down. So Senate Majority Leader Mitch McConnell's decision to allow a vote on an amendment that would extend the Export-Import Bank's charter was too much for Cruz, who said McConnell broke a promise not to do just that and that senators shouldn't "lie to each other."

"We now know that when the majority leader looks us in the eyes and makes an explicit commitment, that he is willing to say things that he knows are false," Cruz said -- potentially violating a Senate rule against attacking other members' motives, and earning a scolding from a handful of senior Republicans over it.

5. The Summer of Trump begins: Attack on John McCain's war-hero status follows "Who's doing the raping?"

JUST WATCHED Donald Trump: 'Somebody's doing the raping' Replay More Videos ... MUST WATCH Donald Trump: 'Somebody's doing the raping' 01:59

Donald Trump had already set off controversy by claiming that many of the undocumented immigrants who crossed into the United States from Mexico were rapists and killers by the time he went on CNN to ask : "Who's doing the raping?"

But he managed to kick the controversy up a notch -- and earn much stronger rebukes from other Republican presidential contenders -- by attacking Sen. John McCain of Arizona, who spent five years as a prisoner of war in Vietnam. Of McCain, he said: "He is not a war hero." Trump went on to insist that veterans who weren't captured haven't received enough attention.

6. Donald Trump gives out Lindsey Graham's cell phone -- and then Graham finds a bunch of ways to destroy it.

JUST WATCHED Trump mocks 2016 opponents, discloses Graham's number Replay More Videos ... MUST WATCH Trump mocks 2016 opponents, discloses Graham's number 02:03

The attack on McCain didn't sit well with one of his best friends in the Senate, Lindsey Graham of South Carolina, who happens to be running for president. After Graham hit back at Trump, the real estate mogul held up a card on which he'd previously written Graham's cell phone number and -- in the middle of a campaign event -- read it to the world.

But Graham would seize on the moment . In a video for IJReview, Graham crushed, pureed and set fire to his famous flip phone. Then he tweeted to ask his followers whether he should get an iPhone or an Android.

7. Chris Christie yells at a gun rights supporter to "name one thing" he's done to oppose the Second Amendment.

New Jersey might not be the nation's most pro-gun state, but Gov. Chris Christie doesn't like to be challenged on his Second Amendment record. He displayed his confrontational style in an Iowa town hall, shouting down a pro-gun activist who asked about the state's restrictions.

"I'm still waiting for one fact from you, one fact about me being anti-gun," Christie scolded the man. "Give me one. One fact. Got one?"

8. Martin O'Malley and Bernie Sanders confront "Black Lives Matter" protesters at Netroots Nation -- and then have to backtrack.

JUST WATCHED Democratic presidential candidates under pressure at liberal event Replay More Videos ... MUST WATCH Democratic presidential candidates under pressure at liberal event 03:11

What would normally be a friendly liberal crowd for Sen. Bernie Sanders of Vermont and former Maryland Gov. Martin O'Malley -- the Netroots Nation conference in Phoenix -- flummoxed both of them when "Black Lives Matter" protesters interrupted their appearances.

O'Malley declared that "black lives matter," but added: "White lives matter. All lives matter." Sanders, meanwhile, shouted down the protesters, complaining that they'd interrupted him. Both later had to apologize.

9. Jeb Bush stumbles over the most predictable question of the entire campaign: Would he have gone to war in Iraq?

JUST WATCHED Can Jeb Bush recover from Iraq war stumble? Replay More Videos ... MUST WATCH Can Jeb Bush recover from Iraq war stumble? 01:54

Former President George W. Bush's reasoning behind his decision to go to war in Iraq -- that the country had weapons of mass destruction -- proved false. So former Florida Gov. Jeb Bush, facing his brother's legacy, had to know he'd be asked whether he'd invade Iraq, knowing what he knows now.

And yet he stumbled in a May interview with Fox News' Kelly . He said he would have gone -- noting that Hillary Clinton voted, too, in favor of the war at the time. What he didn't address, and was then tripped by several more times in the days ahead, is whether he'd have done that knowing everything that's known now. Several days later, Bush finally said he would not have.

10. Rand Paul shushes CNBC's Kelly Evans.

JUST WATCHED Rand Paul's secret weapon: His wife Replay More Videos ... MUST WATCH Rand Paul's secret weapon: His wife 04:56

Sen. Rand Paul of Kentucky looked more than a little prickly -- and raised questions about his treatment of women -- when an interview with CNBC host Kelly Evans went awry. There were several awkward moments, but the one that stood out is when Paul held his finger to his lips and said: "Shhhh."

11. Lincoln Chafee announces his metric platform.

JUST WATCHED Chafee bashes Clinton on war, promotes metric system Replay More Videos ... MUST WATCH Chafee bashes Clinton on war, promotes metric system 04:23

The former Rhode Island governor and senator explained that the metric system worked well in Canada, where he once lived, and could save companies money and help avoid mistakes in measurements and international trade. It's still the most attention Chafee has received during his long-shot campaign.

12. Ben Carson says that some men enter prison straight -- "and when they come out, they're gay."

JUST WATCHED Ben Carson: Prison proves being gay is a choice Replay More Videos ... MUST WATCH Ben Carson: Prison proves being gay is a choice 02:25

Retired neurosurgeon Ben Carson was forced to backtrack within hours after, in a March interview on CNN, he declared that being gay is "absolutely" a choice because "a lot of people who go into prison go into prison straight, and when they come out, they're gay. So, did something happen while they were in there?"

He very quickly apologized, saying he doesn't "pretend to know how every individual came to their sexual orientation." Carson's comments, three months before the Supreme Court legalized same-sex marriage everywhere, also triggered questions for other Republican presidential contenders about whether they believe homosexuality is a choice.

13. Hillary Clinton hits the road in the "Scooby van."

JUST WATCHED Hillary Clinton goes unrecognized at Chipotle Replay More Videos ... MUST WATCH Hillary Clinton goes unrecognized at Chipotle 01:14

When Hillary Clinton ran for president in 2008, her campaign's aura of inevitability ultimately proved fatal. So she was determined to prove that she's willing to earn the Democratic nomination in 2016 -- and started trying to prove it by road-tripping to her first campaign stops in Iowa and New Hampshire.