With less than a month before Americans head to the polls, Donald Trump finds himself confronting an increasingly difficult political environment. His approval rating has fallen to 32%, according to a recent Reuters/Ipsos survey, amid growing dissatisfaction with the cost of living and the ongoing conflict with Iran. More troubling for Republicans is an emerging enthusiasm gap: an October survey found that just 30% of Trump’s 2024 voters were highly enthusiastic about participating in the midterms, compared with 48% of Kamala Harris voters.
Against this backdrop, the 3 November midterm elections have become an important test of Trump’s political standing. With all 435 House seats and roughly a third of the Senate up for election, the outcome will determine the balance of power in Congress for the remaining two years of his presidency.
For investors, however, the more interesting question is whether this political uncertainty will translate into meaningful financial market consequences. The midterms could prove to be a non-event for the broader stock market, yet beneath the surface, their implications for individual industries and US fiscal policy could be considerably more significant.
The Political Landscape
Historically, midterm elections have tended to favour the party outside the White House. Since the Second World War, the president’s party has generally lost House seats, reflecting, among other factors, the electorate’s tendency to reassess the administration’s performance halfway through its term.
Current polling and prediction markets point to three possible outcomes: Republicans retaining both chambers, Democrats gaining control of the House while Republicans retain the Senate, or Democrats securing both chambers.
The implications extend beyond party politics. Congressional control determines the administration’s ability to pass legislation, negotiate government spending and taxation, and advance its economic agenda. A divided Congress would make major legislative changes more difficult, leaving Trump increasingly reliant on executive orders while forcing both parties to negotiate over the government’s budget.
But does a change in congressional control necessarily translate into a change in market fundamentals?
Why Wall Street Might Barely Notice
Despite the considerable political attention surrounding the elections, their impact on the market could be surprisingly limited. A change in congressional control would not necessarily lead to meaningful changes in corporate earnings over the next two years. Even if Democrats secure congressional majorities, Trump’s presidential veto would remain a considerable obstacle to legislation that materially changes the economic environment.
Over the past 60 years, equities have generally experienced modest relative underperformance and slightly higher volatility approaching midterm elections, followed by some normalisation after the vote.
The 2018 midterms provide a useful example. Democrats regained control of the House during Trump’s first presidency, yet the Federal Reserve’s monetary tightening and subsequent policy reversal in 2019 proved substantially more influential for equity performance than the congressional election itself.
A similar dynamic could unfold this time around, particularly with inflation, interest rates and the AI investment cycle continuing to shape the economic outlook.
Nevertheless, a muted response from the broader market does not imply that every industry will be equally unaffected.
Beneath the Surface: The Sector Implications
Healthcare is one example. Medicaid funding and healthcare coverage have become central to budget negotiations. A Democratic-controlled Congress could seek to delay or modify scheduled Medicaid reductions, potentially supporting insurers and healthcare providers exposed to government-funded programmes.
Artificial Intelligence presents another interesting case. Maintaining American leadership in AI enjoys bipartisan support, but the infrastructure required to sustain its expansion is becoming an increasingly sensitive political issue. Data centres consume substantial amounts of electricity, raising concerns about household energy prices, grid capacity and the costs of expanding power infrastructure. At the same time, a Democratic-controlled Congress could push for tighter AI regulation and closer scrutiny of data-centre development. Although significant legislative restrictions would still face Trump’s veto, increased regulatory uncertainty could influence the timing and economics of planned infrastructure investments.
The Hidden Risk of Political Gridlock
While a divided government could limit substantial legislative changes, it may also complicate negotiations over the federal budget. The approaching US debt-ceiling deadline presents one such risk.
The US debt ceiling currently stands at $41.1 trillion, following a $5 trillion increase approved by Congress in July 2025. The increase provided additional borrowing capacity, but much of that headroom has since been consumed by continued federal deficits.
Current projections suggest that the government could reach this borrowing limit during the first half of 2027. The Treasury could then use its cash reserves and accounting workarounds to delay the crisis by several more months.
Should Democrats take control of one or both chambers, negotiations to raise the limit could become considerably more difficult. Both parties could use the deadline to seek concessions over spending priorities, potentially prolonging negotiations.
The 2011 debt-ceiling confrontation provides some historical perspective. Prolonged negotiations brought the US close to its borrowing limit, contributing to financial market volatility and culminating in S&P’s decision to downgrade the country’s sovereign credit rating for the first time.
A similar confrontation in 2027 could create renewed volatility in Treasury markets, with implications for borrowing costs, the dollar and global financial conditions.
The Bigger Picture
The November elections arrive at a politically sensitive moment, with falling presidential approval ratings and growing dissatisfaction over household affordability. Yet their immediate impact on financial markets may prove considerably smaller than their political significance suggests.
The Federal Reserve, corporate earnings and the AI investment cycle could remain the dominant drivers of aggregate equity performance, regardless of which party controls Congress.
However, the implications beneath the headline index deserve closer attention. Healthcare companies could face changes in funding expectations, while AI infrastructure developers may encounter greater regulatory scrutiny.
Meanwhile, a divided Congress could make the approaching debt-ceiling negotiations a more significant source of uncertainty for financial markets in 2027.
The midterms may therefore change relatively little about the direction of the broader market, but they could still influence where risks emerge, which industries face greater uncertainty and how investors navigate the next two years.