In years past, presidential campaigns typically only had to worry about a single so-called "October surprise" with enough firepower to potentially knock them off the the path to 270 electoral votes – George W. Bush's secret DUI arrest and Mitt Romney's "47 percent" video, for instance. But this year, instead of a landmine hidden somewhere in those 31 days, we've essentially had an advent calendar: a new October surprise for almost every day of the month.
Here are the 23 events that shook both campaigns over the last month, including the four bombshells that dropped Halloween night alone.
On the first of the month, The New York Times published a bombshell report indicating Trump managed to lose $916 million in 1995, a spectacular business failure that could have allowed him to avoid paying federal income taxes for at least 18 years.
New York's attorney general's office ordered Trump's personal charity – which the Washington Post had reported was soliciting donations in the state illegally – to cease fundraising in New York immediately.
The Washington Post published a 2005 hot-mic recording that featured Trump bragging about trying (and failing) to sleep with Access Hollywood host Nancy O'Dell and talking about sexually assaulting women. "When you're a star they let you do it. You can do anything – grab 'em by the pussy," he said in the recording.
Shortly after the release of the "Trump tape," WikiLeaks began releasing emails hacked from Clinton campaign manager John Podesta’s personal email account. The emails, which U.S. intelligence agencies believe were delivered to WikiLeaks by a group of Kremlin-aligned Russian hackers, included revelations that former CNN commentator Donna Brazile, now acting chair of the Democratic National Committee, leaked a CNN town hall question to the Clinton campaign in advance of the event.
Ninety minutes before the second presidential debate, Trump held a surprise press conference with three women who'd previously accused Bill Clinton of sexual misconduct, and a fourth woman whose rapist Hillary Clinton represented in court as a public defender. Presumably, Trump's advisers hoped this would shift the attention away from the "grab 'em by the pussy" tape, but as October surprises go, this one was a dud. On a conference call the next day, Speaker Paul Ryan said he would no longer defend Trump, signaling to fellow Republicans it was OK to rescind their support if it would serve them in their districts.
BuzzFeed reported that Trump barged into the Miss Teen USA dressing room while pageant contestants as young as 14 were in various states of undress.
The New York Times reported on two women's allegations of sexual misconduct against Trump. One accused Trump of groping her on an airplane in 1980, and the other of kissing her against her will at Trump Tower in 2005.
People magazine published the first-person account of a reporter who says Trump pushed her against a wall and groped and kissed her while she was working on a profile commemorating Trump's first anniversary with third wife Melania.
The Palm Beach Post shared the story of a Florida woman who said she was groped by Trump at a Mar-A-Lago event in 2003.
CBS News surfaced footage of a 46-year-old Trump leering at a pre-teen girl, then saying behind her back, "I am going to be dating her in 10 years. Can you believe it?"
The Los Angeles Times discovered a clipping containing an anecdote about Trump telling a group of 14-year-old girls, "Just think – in a couple of years I'll be dating you."
A woman told the Washington Post that Trump, whom she did not know, reached up her skirt and touched her vagina at a New York nightclub in the Nineties.
A former Apprentice contestant publicly accused Trump of kissing, groping and thrusting his genitals on her against her will during a business meeting in 2007.
A woman recounted to The Guardian that she attended a 1997 Mother's Day brunch with her family at Mar-A-Lago, where Trump, whom she was meeting for the first time, grabbed her, kissed her and grew angry when she squirmed out of his grasp.
A 10th woman came forward with an assault allegation against Trump; she accused him of leering at her, grabbing her and touching her breast at the 1998 U.S. Open.
An adult film star went public with allegations Trump kissed her against her will and offered her $10,000 for sex.
News broke that Obamacare premiums will increase an average of 25 percent as soon as this month, a development that could hurt Clinton, a vocal supporter of the health care law.
The 2006 Miss Finland told the Finnish paper Ilta-Sanomat Trump groped her the year she participated in the Miss Universe contest.
FBI Director James Comey sent a letter to Congress members, informing them that "an unrelated case" had turned up new emails possibly connected to the agency's Clinton email investigation. Rep. Jason Chaffetz immediately (and inaccurately) tweeted that the investigation had been re-opened. The unrelated case, it was later revealed, was the FBI's investigation into disgraced former Congressman Anthony Weiner allegedly sexting a minor. The emails, which the FBI did not have a warrant to examine at the time of Comey's letter, were believed to belong to Clinton aide Huma Abedin, Weiner's estranged wife.
CNBC reported that Comey had argued against publicly disclosing the FBI's belief that Russia was meddling in the U.S. election. Comey reportedly believed early October would too close to the election to share that information.
A detailed Slate investigation uncovered the existence of a direct communication link between the Trump campaign and the largest private Russian bank – a link the campaign shut down, reopened and shut down again when reporters inquired about it.
Mother Jones reported that the FBI has been investigating a tip that the Russian government has been "cultivating, supporting and assisting" Trump for five years, with the ultimate goal of creating "splits and divisions in western alliance." One of the story's sources claimed Trump was "compromised" on a trip to Russia and that the Kremlin was in possession of information it could use to blackmail him.
The New York Times reported that in the early Nineties, Trump "avoided reporting hundreds of millions of dollars in taxable income by using a tax avoidance maneuver so legally dubious his own lawyers advised him that the Internal Revenue Service would most likely declare it improper if he were audited." According to the Times report, this maneuver – since made illegal – allowed Trump to avoid paying tens of millions in federal taxes.