Behind the Curtain: The new 2024 campaign foretold

Why it matters: They'll unleash their attacks in seven states, but believe three will decide the winner — Wisconsin, Michigan and Pennsylvania.

• The target audience, swing voters, amount to only a few hundred thousand voters inside a tiny sliver of America — basically 6% of six or seven states. They're disproportionately young people, Black men and Hispanic. Many are seen as Trump-curious, but not Trump-sold.
• The Harris campaign is also anxious to re-engage Democratic voters who were down on Biden and might have stayed on the couch.

The big picture: Watch politics through this lens to understand what Trump and Harris do and say in coming months.

• The tiny universe of truly persuadable voters is the reason Harris is very likely to pick a moderate white male as her running mate.
• Look for Trump to visit — or talk incessantly about — the border during the Democratic National Convention, which opens in Chicago next month.

What we're watching: Both candidates expect a small but significant Harris bump coming out of her convention — leveraging her post-announcement momentum, cinematic moments and celebrities to appeal to the swing voters in the swing states above.

• One top Democratic operative said the switch to Harris had been "like a shot of adrenaline to the heart" for the beleaguered troops of the former Biden-Harris campaign in Wilmington, Delaware.

Top Democrats close to her campaign tell us that, at least for now, she's in a virtuous cycle in which she can feed off the euphoria of crowds — the opposite of Biden's predicament — while money and endorsements roll in.

• A senior Democratic official told us that across the country, Democrats "have been waiting to get on the field."

Behind the scenes: We can't stress enough how much President Biden's decision to step aside messed with Trump's plans. Trump advisers thought the race was essentially over if Biden stayed in. They were literally taking swing states such as Arizona off their map, and putting pipe-dream states like New Jersey on it.

• Now some Trump friends wonder if it was a mistake to pick a little-known white guy from a non-competitive state — Sen. J.D. Vance (R-Ohio) — given the new landscape. They also worry his caustic tone and name-calling could backfire if thrown at a woman of color. (Go deeper with Axios' Zachary Basu and Andrew Solender.)

But a top Trump adviser told us Harris is "the only other human being you can 100% tie to Biden and his record." The adviser said the "central reason" Vance was picked was his ability to help the ticket in Pennsylvania, Wisconsin and Michigan — a calculus Harris doesn't change.

• The adviser pointed us to a viral video out yesterday from Dave McCormick, the Republican candidate for U.S. Senate in Pennsylvania, calling Harris "The Most Liberal Nominee In U.S. History," with rat-a-tat clips of her past statements. "That is the playbook right there," the adviser said.

The other side: Harris is enjoying a massive burst of positive coverage as Democrats unite, donors fawn and give, and social media lights up with memes about dancing and laughing, not aging and mental lapses. But that will change.

• Talk to top officials inside the White House, and you understand Harris isn't without substantial risk. Most notably, she hasn't won the loyalty of staffers and advisers, in part because of her instinct to blame others and suspect disloyalty. So she needs to assemble a new team in real time or trust Biden handlers. Remember, one reason Biden was reluctant to leave was his persistent doubt about her electability.

Biden advisers say her propensity to over-prepare to the point of exhaustion portends problems connecting with new voters in an authentic way. 

• A top Democratic operative confirmed all that but added hopefully: "She might gain confidence with the momentum she's got. That could make her easier on staff. And less likely to micromanage."