Since the Iran war resumed, Donald Trump’s net approval has dropped back, and he’s now at a near record low below -20, putting him below other past presidents at this point in their terms.Midterm elections will be held on November 3. Democrats are the slight favourites to gain control of both chambers of Congress. They lead the generic ballot by 6.7 points.While the US stock market has continued to surge, there was a weak jobs report last Friday.Trump’s ratingsIn analyst Nate Silver’s aggregate of US national polls, Trump’s net approval is -20.4, just above a record low this term of -20.6 on July 30. Currently, 58.5% disapprove of his performance and 38.1% approve.Trump’s net approval had recovered from a low of -20.2 in late May to -16.6 on July 13. But the resumption of the Iran war has pushed his ratings down again.Trump’s net approval is below what any past president since Harry Truman had at this point in their term, with Joe Biden the closest at -15.2.On four issues tracked by Silver, Trump’s net approval is -12.4 on immigration, -23.7 on trade, -29.9 on the economy and -42.3 on inflation. Since mid-July, Trump’s net approval on the economy and inflation have slumped six points, while his net approval on immigration and trade have been relatively stable.Silver also has an aggregate of US support for the Iran war. Currently, 56.7% are opposed to the Iran war while 37.1% support it, for a net support of -19.6. Net support has increased from a low of -26 in mid-July.Midterm elections this NovemberAll 435 federal House of Representatives seats and 35 of the 100 senators will be up for election at November 3 midterm elections. In 2024 elections, Republicans won the House by 220–215 over Democrats and the Senate by 53–47. Owing to Vice President JD Vance’s potential tie-breaking vote, Democrats need at least a four-seat gain to win Senate control.I previously wrote that, owing to Republican gerrymandering, Democrats need at least a four-point margin in the generic ballot to have a good chance to win the House majority. The Senate is more skewed to Republicans as every state has two senators. Democrats need a double-digit margin in the generic ballot to win the Senate on a uniform swing.In Silver’s aggregate of the generic ballot polls, Democrats lead Republicans by 48.4–41.8, a 6.7-point margin. Democrats’ lead had peaked at 7.1 points in late May, but fallen back to 5.9 points on July 22.Silver has just launched his midterm election forecast model. The generic ballot in this forecast gives Democrats an 8.1-point lead, owing to using likely voter polls. Democrats are more likely to vote at lower turnout elections like the midterms than Republicans, when Trump is not on the ballot.The model gives Democrats a 57% chance to win the Senate and an 86% chance to win the House. Overall probabilities of control are 56% for Democrats winning both the House and Senate, 30% a Democratic House but Republican Senate and 13% that the Republicans hold both the House and Senate.While uniform swing indicates that Democrats need a double-digit margin in the generic ballot to win control of the Senate, Silver’s model has Democrats as the favourites to win with a 6–7 point margin in the generic ballot. In the House, Democrats are favourites if they win by 3–4 points.While Democrats are the slight favourites in the Senate, they are at risk of losing one of their own seats. In Michigan, left-wing Democrat Abdul El-Sayed won the August 4 primary, but he currently trails Republican Rogers by 1.6 points in general election polls. As Senate elections are strongly correlated with presidential approval, Silver’s model expects El-Sayed to underperform other Democrats in November, but still win.Democrats have leads of three points or less in Texas, Ohio and Alaska and are behind by 0.3 points in Iowa. Trump won all these states by double-digit margins in 2024. This explains why Democrats are the slight favourites to gain control of the Senate.The two key items that could go wrong for Democrats are a markedly improved economy by November for most Americans, not just the stock market, and a systematic error in which Republicans overperform the polls.Weak jobs numbers and other economic indicatorsThe US July jobs report was released last Friday. For the establishment survey, 23,000 jobs were lost, and the May and June jobs added were revised down by a total of 103,000.For the household survey, while the unemployment rate dropped 0.1% to 4.1%, this was owing to a fall in the participation rate. The employment population ratio (the percentage of eligible Americans who are employed) dropped 0.1% to 58.9%.In January 2025, when Trump replaced Joe Biden as president, the employment population ratio was 60.1%. It’s now at its lowest since September 2021, when the economy was recovering from COVID. In Australia, the employment population ratio was 64.0% in June.Another sign of US economic weakness was the June report on personal income and expenditure. Since January, every month has had greater expenditure than income, pushing the personal savings rate down 1.7 points since January to 2.7%, the lowest it has been since June 2022.Despite the continued closure of the Strait of Hormuz, the benchmark US S&P 500 stock market index has surged 5.6% since July 29, to be just 0.4% below its record high reached last Friday. The S&P is 11.3% above the level it was at in late February, before the Iran war began and 17.2% above its late March low.While consumers have been hurt by high fuel prices, the stock market has surged owing to the AI boom. The weak jobs numbers helped the stock market as they mean interest rates are less likely to rise.Adrian Beaumont does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.