Democrats are heading into the U.S. midterm elections with their largest polling advantage of the campaign. Since September 1, the party has gained roughly three points in voter intention, according to polling averages, putting it more than eight points ahead in the generic congressional ballot.

The generic ballot asks voters which party they would support for the House of Representatives rather than focusing on individual candidates. Its results point to a possible “Blue wave”, although uncertainty remains over the reliability of the polls. President Donald Trump has presented the elections as a referendum on his leadership and repeatedly urged voters to act as if he were on the ballot.

Trump has held 28 rallies over the past two months, concentrating on states that would normally be considered safe Republican territory. Analysts disagree over the strategy: some see it as evidence of weakness surrounding Trump’s political brand, while others interpret appearances in states such as Texas, Iowa and Kansas as a response to unexpectedly difficult Senate races.

Trump’s approval rating remains low. Some polls place it only slightly above 30%, while the EL PAÍS aggregator puts his popularity at 37%. Democratic campaigns have focused on economic conditions, arguing that the administration has not delivered the relief promised in 2024, as well as on the war in Iran and its effect on fuel prices. Allegations of corruption involving the administration and the president’s family have also become a more prominent concern among voters.

The House of Representatives has long been viewed as the chamber most likely to change hands. Republicans currently hold 218 seats, compared with 214 for Democrats, one independent and two vacancies. Polling projections give Democrats an estimated gain of 18 seats, which would provide a comfortable majority. No forecast assigns the party less than an 80% chance of winning the chamber.

The Senate race has become more competitive since the primary elections ended during the summer. Democrats need to reclaim several states that Trump won by more than 10 points over Kamala Harris in 2024. However, the president’s unpopularity and a group of candidates selected with his backing have improved Democratic prospects in key contests, including those involving Ken Paxton in Texas and Darlene Graham in South Carolina.

Aggregated polls project that Democrats will flip five Republican-held Senate seats. Five other Republican seats are considered within the margin of error or effectively tied. Experts caution that polling errors can occur together and may favor the same party across multiple races.

The contests remain difficult to assess nationally because voter concerns vary significantly from state to state. Still, most of the Democratic candidates leading in the polls have adopted a broadly centrist approach, including Adam Hamilton in Kansas and Mary Peltola in Alaska. Abdul El-Sayed in Michigan is a notable exception as a progressive candidate seeking to become the first Muslim senator in U.S. history.

Late developments could still affect the outcome. In Alaska, a dispute over a second candidate named Dan Sullivan has drawn attention after the Justice Department sought to have votes for him discarded. The New York Times later reported that Peltola’s campaign had encouraged the candidate to enter the race. A judge rejected the Trump administration’s request to block the results, but the episode could still damage Peltola politically.

Michigan has also seen a significant shift. Haley Stevens, who lost the Democratic primary, ultimately endorsed Republican Mike Rogers instead of El-Sayed after a series of changes in position. El-Sayed leads the polls by more than three points, but the break with Stevens could cost him support among her backers.

Democrats are broadly confident, though they remain wary of polling failures from the past decade, including errors that underestimated Trump’s electoral strength. Senator Raphael Warnock of Georgia described his party as “nauseatingly optimistic” in comments to CNN. Even so, the current Democratic lead is considered substantial enough that a two-point polling error in favor of Republicans could still leave Democrats with majorities in both chambers of Congress.

Sources: El País Internacional.