US midterms: the Iran war and the cost of living decide Congress

The United States holds its midterm elections on Tuesday. All 435 House seats are up, along with 35 Senate seats and 36 governorships. The vote comes with more than 57 million early ballots already cast — against 46 million at this stage in 2022 — and with the Iran war in its eighth month, according to the University of Florida Election Lab and data reported by AP and CBS.

What is being voted on and how the campaign stands

Control of Washington is narrow. Republicans hold the House by 219 seats to 214 Democrats, with two vacancies, and the Senate by 53 to 47. The majority is 218 and 51. Democrats need a net gain of three seats in the House and four in the Senate, according to AP, with several of the tightest races in states Trump won in 2024. NBC News rates a dozen districts and five Senate seats as toss-ups.

It has been the most expensive cycle on record: more than $11bn in political advertising, according to AdImpact, cited by Time. Add to that a round of mid-census redistricting that the National Conference of State Legislatures says has not been seen since the 1800s, and unusually high turnover on Capitol Hill. The Supreme Court on Monday rejected the Trump administration's bid to set aside 20,000 mail-in ballots in California, a decision that lands with the country waiting on the count.

Early voting has passed 57 million ballots, according to the University of Florida Election Lab: 32 million in person and 25 by mail. At this stage in 2022, 46 million had voted. Trump arrives with 38% approval and 60% disapproval in NBC News's average, with inflation and petrol prices the main concerns. On Monday, petrol stood at $4.17 a gallon, 23 cents below a month earlier but $1.13 above a year ago.

The war that has defined the campaign

The war began on 28 February, when the US and Israel launched an offensive that killed Supreme Leader Ali Khamenei. Eight months on, the conflict is unresolved. Washington maintains a naval blockade to stop Iranian oil reaching the market, thousands of troops remain in the waters off the Middle East and a third aircraft carrier is heading to the region. Iran has cut exports through the Strait of Hormuz, which carried about 20% of the world's oil before the war.

The cost shows at the pump and in the markets. Brent closed on Monday at $104.77, down 7.6%, and WTI at $96.46, after signals of negotiations; even so, crude is up about 45% since February. Diesel, more exposed to the Ukraine war and attacks on Russian refineries, remains at $6.29 a gallon, 77% higher than at the start of the year.

The eve of the election showed the war is not over. The US launched "limited defensive" strikes on Iranian targets near the Strait of Hormuz after the Revolutionary Guard fired at an American aircraft; Iranian state television reported five explosions on Qeshm Island. Tehran says "the ball is in Washington's court" and that its seven-step plan could be implemented within two days: reopening Hormuz and resuming nuclear talks. Qatar is mediating between the parties. Trump says a deal "could happen"; Netanyahu is pushing for another wave of strikes after the election, while Israel remains without a clear government after the 27 October vote.

The map: civil nuclear power, not the military programme

The map colours the 30 countries that generated nuclear electricity in 2025, according to Our World in Data and Ember. The darker the country, the more terawatt-hours it produces. It does not measure arsenals or centrifuges: it measures civil nuclear power, the kind that feeds the grid. That distinction matters in a war fought partly over Iran's nuclear programme.

The United States is the largest producer: 784.8 TWh, 17.4% of its electricity and 2,260 kWh per person. China follows (487.6 TWh, though only 4.6% of its mix), then France (392.1 TWh and 68.8% of its electricity) and Russia (218.7 TWh, 18.3%). Iran, by contrast, generates 7.3 TWh, 1.9% of its electricity and 79.5 kWh per person: less nuclear electricity than Mexico (10.2 TWh) and far behind the big producers. Its weight in the war comes not from electrons but from geopolitics and the military programme.

Washington argues that the offensive destroyed Iran's nuclear programme and demands a "firm and verifiable" guarantee that Tehran will not rebuild it, in the words of Vice-President JD Vance. Iran insists its programme is civilian. The map does not settle that dispute, but it scales the visible part: Iran's civil nuclear output is small and predates the war. What is at stake in Hormuz and in the talks is not measured in terawatt-hours.

A world at war

The Iran war is not the only front. In Ukraine, Russian attacks on the power grid have left hundreds of thousands of homes without electricity across several regions, and a strike on an aid distribution centre in Komyshuvakha, Zaporizhzhia, killed at least 26 people, according to Ukrainian authorities. Washington has announced trilateral talks with Kyiv and Moscow in Abu Dhabi on 10 and 11 November.

In Gaza, the ceasefire remains fragile: Israeli strikes killed at least eight people on Sunday, according to health sources, and more than two million Palestinians still depend on limited aid. In Sudan, the civil war between the army and the Rapid Support Forces has left 8.6 million people internally displaced and 19.5 million face a food crisis; drones have hit the power grid in at least nine states. Myanmar, Yemen, Haiti and Colombia complete a map of conflicts that shares a pattern: attacks on energy infrastructure, displacement and pressure on prices.

What comes next

The polls close tonight and results will emerge overnight on 3 to 4 November, Central European Time. The 120th Congress is sworn in in January. If Democrats take the House, the war and its costs will face a platform of oversight; if Republicans hold, pressure to end the conflict will be lower, though the war remains unpopular.

In Iran, the decision could come within days. Trump says a deal "could happen"; Tehran wants Hormuz reopened and the nuclear programme on the table; Netanyahu is betting on more strikes. Oil and petrol prices react to every headline, and voters notice. The civil nuclear map will not change with the count, because it uses 2025 data, but it helps show what is and is not at stake.

The campaign has been a referendum on two things visible in the fridge and at the pump: the war and the cost of living. The map adds the context missing from the debate: civil nuclear power is a small part of the Iran problem. The answer will come from the ballot box and, after that, from diplomacy.