Democrats Hope for Midterm Gains, but Polls Have Misled Them Before
Polls ahead of the 3 November US midterm elections point to a Democratic advantage, but surveys have underestimated Republican support in the past. Analysts cite several reasons Democratic gains could be smaller than expected.
The US Democratic Party is heading into Tuesday's midterm congressional elections, on 3 November, with high hopes. Polls suggest the party, currently in opposition, could win back control of the House of Representatives and compete strongly for seats in the Senate. The reasons cited are the historically low popularity of Republican President Donald Trump and public frustration over rising food and household costs.
According to the polls, Democratic candidates lead in well over the 218 seats needed for a majority in the House, the lower chamber of Congress. In the key Senate races they are tied or narrowly ahead. A New York Times poll showed a tie in South Carolina, a state Trump won by 18 percentage points in 2024, while CNN surveys put Democrats ahead in Texas, Kansas and Maine.
A record of polling misses
Recent US history has examples of polls, even those taken days before voting, missing the mark. Trump outperformed forecasts in winning in 2016 and 2024, and his narrow 2020 loss to Democrat Joe Biden came after most surveys had indicated a more comfortable Biden win. This year, polls suggested Abdul El-Sayed was heading for a double-digit win in Michigan's Democratic Senate primary, but the margin was 1%. In Wisconsin's Democratic gubernatorial primary, a candidate who led by nearly 20 points lost by a fraction of a percent.
Clifford Young, president of Ipsos Public Affairs, says polling has become harder because Americans are more difficult to reach and many of those contacted are less willing to take part. He argues conservatives are more anti-establishment and often do not participate. If Republican voters are systematically undercounted and models do not account for it, the data could skew toward Democrats.
Why gains might be smaller
Midterm polls have been more accurate in recent years, partly because Trump was not on the ballot. The president's party commonly fares badly in midterms; in 2010 Republicans flipped more than 60 House seats. This time, Democrats' gains could be limited because much of the contested territory was won easily by Trump in 2024, House boundary changes mean fewer seats switch parties, there are fewer swing voters, and Republicans hold a cash advantage for attack ads.
Young believes pollsters are doing a better job, but some uncertainty will always remain, since they are dealing with people.
