An already-turbulent Republican presidential contest seemed poised to fly apart on Friday. Retired neurosurgeon Ben Carson, now just edging Donald Trump for the polling lead in the race, melted under the new glare. In the space of a week, he insisted, despite reports suggesting otherwise, that as a kid he had in fact tried to attack his mother with a hammer and stab someone, and that any attempt to deny those stories amounted to a “smear” (huh?); stood by his contention that the Egyptian pyramids were built by the Biblical figure Joseph for grain storage rather than interring pharaohs; and then, Friday, after a bizarrely churlish CNN interview, found himself in a firestorm over whether he lied about receiving a scholarship offer from West Point.

It may be that early-state voters are looking for a violent juvenile sociopath who mellowed into an armchair Egyptologist. Or, likelier, a crowded field is growing more unstable as the first events on the primary calendar swing into view.

Lost somewhere in the contest’s bulging middle tier is Carly Fiorina, the former Hewlett-Packard CEO who vaulted into serious contention after a pair of standout debate performances. But she collapsed as quickly as she rose without so much as offering a theory about a treasure map on the back of the Constitution. What happened? One explanation, from veteran political handicapper Stu Rothenberg: In a race stratified between the “outsider” and “establishment” lanes, Fiorina doesn’t quite fit in either. She’s adopted the hot rhetoric of someone tilting against the mainstream order. Yet her CV, the spine of her argument that she’s equipped to shake things up, indicates she’s a product of it. (And she’s no stranger to Washington, having served as an advisor to Sen. John McCain’s 2008 presidential campaign, as a fundraising chair for the Republican National Committee, and on an external advisory board for the CIA, while owning for a time a condo at the Residences at the Ritz-Carlton in the city’s West End.) “She lacks a message,” Republican pollster Glen Bolger says. “And when you say that your strength is running HP, and by all accounts it was not a success, eventually that gets around. Why would Republicans back a candidate who has a glass jaw?”

Fiorina has room to recover the ground she’s lost. The latest NBC/ Wall Street Journal poll showed more Republican voters than not said they could see themselves voting for her — a distinction only four other candidates notched. And she continues to register near the top of the heap in focus groups. That underlying appeal could earn her a second look in a roiling race. Her bid’s fundamental deficiencies suggest she’d struggle to close the sale.

Top News

• Obama nixes the Keystone XL pipeline

President Obama on Friday formally rejected the proposal to build the Keystone XL oil pipeline. The project took on outsize significance in recent years as a symbol in the struggle between the fossil fuel industry and environmentalists. The pipeline would have allowed producers to send crude from oil sands in Alberta, Canada to Gulf Coast refineries. Some observers speculated that Obama could simply decline to issue a decision on the matter, leaving it to his Oval Office successor. But his move to nix the project signals an interest in codifying an environmental legacy he's also pursuing through clean air regulations and an international accord to curb carbon emissions.  Fortune

• Speaker Ryan notches his first win

It may be no great shakes in the scheme of things, but in his first week on the job, House Speaker Paul Ryan managed to corral the unruly mob that makes up the lower chamber into passing a multi-year highway bill — a feat no other House leader has managed in a decade. The package included an provision to revive the Export-Import Bank, whose charter Tea Party-affiliated conservatives forced to expire over the summer. Ryan pointed to a more inclusive process he's pledged to make a hallmark of his leadership as enabling the win.  Politico

• Rubio's financial struggles break through

It's never a good sign for a candidate when People magazine is drilling down on alleged financial improprieties. But chalk up that sort of scrutiny to the wages of rising in the polls. Florida Sen. Marco Rubio, newly ascendant in the GOP presidential field, is facing questions about his personal finances during his years as a Florida state legislator. At issue are personal charges that Rubio appears to have piled up on official credit cards. Rubio avers that all the expenses were above-board and repaid, and he's pledged to release records backing up the claim soon.  People

Around the Water Cooler

• In Bush v. Rubio, the mentee surpasses the mentor

Among all the other crosscurrents buffeting the Republican presidential race, none may prove more consequential than the switch Sen. Marco Rubio is now engineering with his one-time mentor, former Florida Gov. Jeb Bush. The former frontrunner’s campaign is trying to brace donors and reporters for the polling gulch that Bush now finds himself in after a dismal performance in the third GOP debate. Rubio — shiny, new, and packing major horsepower on the stump — meanwhile is steadily rising. Most troubling for Bush, he’s now registering just 7 percent in his home state, while Rubio’s pulled ahead of him there by 9 points. Both campaigns acknowledge that between the two of them, there’s only one ticket out of the state’s March 15 primary. Fortune

• Jeb's last name is dragging him down at exactly the wrong moment

On the ropes in a presidential race he was once expected to dominate, the last thing Jeb Bush needs as his campaign reels is a messy explosion of old Bush family psychodrama in the public sphere. And yet that's just what he's getting with the imminent publication of a George H.W. Bush biography already tearing open wounds among the outsize figures that populated the presidencies of his father and brother. The book, Destiny and Power: The American Odyssey of George Herbert Walker Bush, features some splashy accusations from Poppy Bush himself about how badly served George W. Bush was by Dick Cheney and Donald Rumsfeld, prompting headline-grabbing responses from both. Jeb, desperate to demonstrate he's a 21st century leader, can't be pleased.  Slate

• The hidden code that stacks the Republican primary against conservatives

The GOP presidential race may look like an even-money fight between the forces of hard-right conservatism and those representing what today passes for the more moderate establishment. It's not. The vagaries of the process for awarding delegates — which will determine who ultimately emerges with the nomination — are embedded with huge advantages for the moderate candidate. The key is the weight wielded by Republican voters in states too blue to factor into the general election itself.  FiveThirtyEight

• Rand Paul's new book is selling abysmally 

A year ago, Kentucky Sen. Rand Paul looked to have captured the imagination of a new generation of conservatives with a libertarian-tinged message primed to rock the presidential contest he was about to join. In one of the bigger surprises of a race with no shortage of them, Paul since has flamed out epically, barely registering as a blip in polls. The latest evidence comes from the less-than-meager sales his new book is posting, with a mere 80 sales in its first six days. Did the debate move away from his qualified isolationism as ISIS and other threats rose? Was it a failing of his organization? Some combo thereof? The autopsy is yet to be written, but it is pending.  BuzzFeed