Just last week, a supremely confident Donald Trump was at the center of the political universe — soaking in a raucous atmosphere at the GOP convention after narrowly surviving an assassination attempt.

• This week, it's Democrats — not Republicans — whose party is riding a historic sugar high, Axios' Zachary Basu writes.

Why it matters: Vice President Kamala Harris is reveling in record fundraising, an early bump in the polls, and a growing grassroots army.

• It's a honeymoon of epic proportions — but one the Trump campaign is betting won't last.

📊 State of play: A New York Times/Siena College poll out yesterday found Harris trailing Trump by just 1 point among likely voters nationwide, closing the 6-point gap Trump recorded over President Biden in early July.

• Trump pollster Tony Fabrizio predicted in a memo this week: "Before long, Harris' 'honeymoon' will end and voters will refocus on her role as Biden's partner and co-pilot."

🖼️ The big picture: After weeks of division and despair over Biden's candidacy, the Democratic Party's rapid consolidation behind Harris cleared the way for an unprecedented election sprint..

• Between Sunday and Tuesday, the Harris campaign says it raised a staggering $126 million — much of it from small-donor donors contributing for the first time.
• Democratic megadonors who had turned their backs on Biden were suddenly energized, rushing to host glitzy fundraisers and write massive checks.

Zoom in: Harris' public appearances this week have reflected that enthusiasm.

• In Wisconsin on Tuesday, she held the campaign's biggest rally ever, according to campaign manager Jen O'Malley Dillon.
• In Indianapolis on Wednesday, Harris delivered a speech to a historically Black sorority as part of a push to galvanize a demographic long described as the "backbone" of the Democratic Party.
• In Houston yesterday, Harris' remarks to the American Federation of Teachers were delayed several minutes because of the crowd's incessant cheering.

What to watch: With the new-look Democratic campaign less than a week old, Harris allies see ample opportunities for sustained momentum.

• Interest has surged around her search for a running mate. The Democratic convention, kicking off 24 days from now, is expected to be a festive celebration of the party's new leaders.

📺 Reality check: Republicans are preparing to blanket the airwaves over the next several weeks in hopes of bringing the Harris honeymoon to an abrupt halt.

• Trump and allies were booked to outspend Harris' team 25-to-1 on TV and radio ads — more than $68 million for Republicans compared to just $2.6 million for Democrats — in the period that began Monday, the day after Biden stepped aside, through the end of August, according to an AP analysis of data from the media tracking firm AdImpact.

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Former President Obama and First Lady Michelle Obama this morning became the final high-profile Democratic leaders to publicly back Vice President Harris.

• Why it matters: The Obamas will add star power to Harris' campaign, which picked up the party's support with stunning speed and efficiency after President Biden stepped aside, Axios' April Rubin writes.

Obama said in a campaign video: "We are gonna do everything we can to help propel you into the presidency and continue the amazing legacy that Joe Biden and you have been able to establish.

• "Michelle and I couldn't be prouder to endorse you and to do everything we can to get you through this election and into the Oval Office."

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Bulletin: Hours before the Olympics' grand debut, France's high-speed rail network was hit with widespread "criminal" sabtoage, including arson attacks. Travel to Paris was blocked from across France and Europe.

• The disruptions are expected to endure through the weekend and possibly longer, officials said.
• Eurostar rail service between London and Paris was disrupted by the vandalism. Passengers were asked to postpone journeys. Get the latest.

📱 For today's Opening Ceremony, 200+ Samsung smartphones will provide a unique lens to viewers as athletes from around the world travel by boat along the Seine River, Axios' Ina Fried writes from Paris.

• The ceremony will take place outside a stadium, on the waters of the Seine — creating a beautiful backdrop, but necessitating a different approach to capturing the event for a TV audience.

Traditional cameras will be used to provide wide shots. The Samsung Galaxy S24 Ultra devices mounted on each of the 85 boats will provide an up-close view of the athletes as they make their way down the Seine.

• Footage will be sent over a private 5G network, with antennas placed along bridges on the route. Keep reading.

👀 How to watch: Live coverage starts at noon ET today on NBC. The opening ceremony starts at 1:30 p.m. Schedule + streaming services.

🏊 Weekend watch list: Katie Ledecky's first medal shot (Saturday, 2 p.m. ET) ... Street skateboarding finals (Saturday, 11:30 a.m. ET) ... Simone Biles returns (Sunday, 5:40 a.m. ET). Full guide from Axios' Maxwell Millington.

Vice President Harris' entrance into the race has all but killed one of this election cycle's most-talked-about groups — the "double haters," who dislike both candidates, according to a new N.Y. Times/Siena College poll.

• Why it matters: Until last week, an unprecedented share of voters held unfavorable views of both President Biden and former President Trump.

Biden is now out of the race. Trump's approval numbers are at their highest level ever recorded by a Times/Siena poll.

• Harris has also gained 10 points since February.

🧮 By the numbers: "With both Ms. Harris and Mr. Trump riding high, the number of voters who dislike both candidates has plunged to 8 percent, down from 20 percent in Times/Siena polls so far this year," N.Y. Times polling guru Nate Cohn writes.

• Keep reading (gift link — no subscription required).

Israeli Prime Minister Benjamin Netanyahu was upset by Vice President Harris' statement after their meeting — and is concerned it will harm the negotiations over Gaza, an Israeli official told reporters.

• Why it matters: Harris' meeting with Netanyahu — her first with a foreign leader since launching her campaign — took place at a critical moment in negotiations over a possible deal, Axios' Barak Ravid writes.

After a 40-minute meeting, Harris said she pressed Netanyahu to conclude a hostage and ceasefire deal.

• "It is time for this war to end in a way where Israel is secure, all the hostages are released, the suffering of Palestinians in Gaza ends and the Palestinian people can exercise their right to freedom, dignity and self-determination," she said.

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OpenAI's announcement of SearchGPT — yesterday's direct shot at Google
— kicks off the next phase of the search industry's rapid AI remodel, Axios managing editor for tech Scott Rosenberg writes.

• Why it matters: Tech leaders believe traditional search engines will give way to ChatGPT-style conversational interfaces as the dominant mode of information gathering online.

🎨 The big picture: Google and Microsoft, the only major players left standing in the traditional search business, have already woven generative AI into their search engines, with mixed results.

• OpenAI's new offering promises to cite and link to sources and to let users refine their inquiries.

🔭 Zoom out: OpenAI and its rivals are all betting that most users would rather just ask a question and get it answered than dig through search results.

• That makes sense for casual queries and simple facts ("What time is the Super Bowl?"). But AI search summaries like Google's have so far fallen down when faced with complex topics, controversies and ambiguities.

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The talk of S.F. ... Mike had meetings yesterday with two AI experts, and they both brought this up:

Two AI systems from Google DeepMind — an AI lab in London — were able to solve four of six tricky problems from this year's International Mathematical Olympiad (IMO).

• That's on par with silver medalists in the annual world math championship for high school students, Axios' Alison Snyder writes.

Why it matters: The ability to solve a range of math problems in step-by-step proofs is considered a "grand challenge" in machine learning, and has been beyond the reach of current state-of-the-art AI systems.

• "These are extremely hard mathematical problems and no AI system has ever achieved a high success rate in these types of problems," said Pushmeet Kohli, vice president of research focused on AI for science at DeepMind.

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NBC is betting on an Olympics-sized TV ratings rebound now that the Games are free of COVID-era disruptions, coupled with the scenic backdrop of Paris, Tim Baysinger writes in Axios Pro: Media Deals.

• Why it matters: If the Olympics audience keeps dwindling, NBC's $7.8 billion rights deal to televise the Games through 2032 starts to look like an albatross.

🔢 By the numbers: The Tokyo Olympics, which were delayed by a full year and held without any spectators due to COVID restrictions, were the worst-performing Games since NBC took over in 1988.

• Perhaps more troubling is that it was the second consecutive Summer Olympics to see viewership decline.

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