Four weeks out from the election, and for most Americans, it’s time for football, foliage and flannel. For politics watchers, all eyes are on an October surprise. They’ve been game-changers before.

In 2008, the collapse of Lehman Brothers, which ushered in the biggest financial crisis since the Great Depression, was a turning point in John McCain’s presidential campaign. He was even with Barack Obama when the news broke, then trailed in every survey after. He lost the popular vote by seven points.

Surprises have come from home and abroad. In 1980, it was President Jimmy Carter’s inability to resolve the Iranian hostage crisis. Eight years earlier, it was President Richard Nixon’s announcement that "peace was at hand" in Vietnam.

Some have more impact than others. It’s not clear that news about George W. Bush’s DUI changed much about the 2000 election, nor that James Comey’s letter to Congress about Hillary Clinton’s email server was the decider in President Trump’s 2016 win.

Still, these surprises all have one thing in common: they happened in presidential years.

EXPLOSIVE SLEEPER ISSUE COULD FUEL MIDTERM SHAKEUPS, TOP REPUBLICAN PREDICTS: ‘YOU’RE GONNA SEE SURPRISES’ It’s not as though we don’t get breaking news during the last month of a midterm cycle. Take 2018, when the GOP warned about a migrant caravan, Brett Kavanaugh sought a seat on the Supreme Court, and a gunman opened fire at a Pittsburgh synagogue.

But that was the exception, not the rule. For the most part, midterm October surprises affect individual races, not the overall trajectory of a party.

In the last midterm, for example, Herschel Walker faced damaging allegations about paying for former girlfriends’ abortions, while in Florida, the destruction caused by Hurricane Ian gave Gov. Ron DeSantis the opportunity to show Floridians that he could be trusted to handle a crisis.

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Voters haven’t changed their minds about Trump or the party they’d prefer to elect to the House for several months now, so local stories like these are the ones to watch in the final weeks of the campaign. Besides, the biggest surprises come after October.

For what still looks like a good – maybe great – year for the Democrats, the party is playing defense in some unexpected places.

DAVID MARCUS: IN DEEP BLUE MINNESOTA A RED DAWN MAY BE RISING AHEAD OF THE MIDTERMS That starts with Minnesota, where Republicans have a star candidate in Michele Tafoya. The former NFL sideline reporter has been up and down the state with a message to "stop the fraud" if elected to the Senate. That’s been a hot issue in the state, and it’s allowed her to target the Democrat, Peggy Flanagan, who currently serves as lieutenant governor.

Then there’s New Hampshire, another state where Democrats are in the driver’s seat thanks to this political environment, but where the GOP has a favorable match up. Former U.S. Senator John E. Sununu is back on the ballot this year against Chris Pappas, who seems to have had trouble animating his voters. Even Oregon’s gubernatorial race is competitive this year. Meanwhile, Republicans are spending money in surprising places.

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In Arkansas, Sen. Tom Cotton has thrown $13.6 million at his reelection bid, outspending his Democratic opponent Hallie Schoffner 65 to 1. Cotton may have ambitions beyond his current role in the Senate, but in 2020, his spending fell short of $1 million.

Idahoans got a letter in the mail from Vice President Vance last month warning them that Democrats could "pour millions of dollars" into independent challenger Todd Achilles; Vance called it an "urgent national race." Mississippi Sen. Cindy Hyde-Smith has been running ads attacking her Democratic challenger Scott Colom in recent weeks, calling him a "failed prosecutor" with a "chilling" record on crime; that state has seen $5 million in ad spending so far this year.

FOX NEWS POLL: IT’S A LONE STAR SENATE SHOWDOWN BETWEEN TALARICO AND PAXTON And Florida is full of election surprises. In 2018, Rick Scott won his Senate race by 0.1 percentage points while DeSantis won his by 0.4 points. Two years later, the presidential race was decided by just 3.4 points.

Nebraska and South Dakota could be closer-than-expected for Republicans as well.

In this week’s Power Rankings, one Carolina gets more competitive while another drifts away from the GOP, and Democrats get nervous about a governor’s race in Oregon.

The math is the same in the Senate. Each party has 47 seats to their name, leaving six toss-up races to determine control. Those are Alaska, Iowa, Maine, Michigan, Ohio, and Texas, which all look close in the flurry of surveys released by pollsters last week.

Two other races are highly competitive: New Hampshire (Lean D) and Kansas (Lean R). On the polling alone, these look more like toss-up states: surveys released last week have the Democrat ahead by only five points in New Hampshire, and the Kansas race dead even. It’s the partisan makeup of these states that keeps them at "lean." North Carolina is less competitive than it was two weeks ago.

Fox News confirmed on Friday that the Senate Leadership Fund, a powerful Super PAC aligned with Republican leadership, was pulling resources from the state. Earlier, Sen. Tim Scott left it off a list of states where Republicans were focusing spending.

GOP nominee Michael Whatley is running as strong a race as he can there, and the margin will probably be tighter than polls currently have it. But the Democrat, Roy Cooper, is also a strong candidate, and he has had double-digit leads in multiple surveys.

North Carolina moves from Lean D to Likely D.

Nearby South Carolina is getting more competitive. Darline Graham, appointed to the Senate after the death of her brother, Lindsey, is reportedly getting more help on the campaign trail from President Trump.

There are lingering questions about Graham’s ability to turn out a broad spectrum of Republican voters against a Democratic candidate who, like her counterparts in Kansas and Nebraska, is pushing hard on the price of diesel.

The state moves from Solid R to Likely R.

Four years ago, Oregonians sent Tina Kotek to the governor’s mansion for the first time, and it hasn’t gone smoothly.

Kotek faces four issues all at once in this campaign, as outlined in local reports and on the trail: a housing crisis, poor education outcomes, higher city crime rates than in neighboring states, and like other incumbents, she flip-flopped on data centers. A lethargic debate performance last week didn’t help matters.

Drazan has lost this race before, and this time, won’t get help from a third-party candidate who drew votes from the Democrat. But this time around, she has created more distance both from Trump and conversations about abortion, which she calls a "settled issue." Democrats have every reason to hold on to this state in November, but it’s going to be tougher than the party wants. Oregon moves from Likely D to Lean D.

Elsewhere, two states are becoming more competitive for Democrats, beginning with Florida.

The Sunshine State is the home of the "MAGA" movement, and Rep. Byron Donalds easily locked up the Republican nomination in August. But he has stumbled, at times, on the campaign trail, and Hispanic voters continue to express frustration with this economy. Florida moves from Solid R to Likely R.

And in Vermont, longtime incumbent Republican Phil Scott might have raised an eyebrow at a new poll from the University of New Hampshire showing his Democratic opponent, Amanda Janoo, up six points against Scott, 49% to 43%.

Scott keeps winning elections comfortably in Vermont, but the party label could be a bigger problem this cycle. The Green Mountain State also moves from Solid R to Likely R.