The US midterm election season has entered its final stretch, with Wall Street scrambling to prepare for every possible outcome. Yet in a fortunate twist, the best-case scenario for markets appears to be the most probable one. Investors are increasingly convinced that Democrats will secure the House in November, while Republicans hold a slight edge in the Senate. For many market observers, this is the ideal setup, carrying the lowest risk of disruptive policy shifts.

Confidence in this outcome, while not baseless, remains far from certain. Prediction markets show Democrats as heavy favorites to take control of the House, but the Senate race has intensified, with Republicans holding only a narrow lead on platforms like Kalshi and Polymarket. Brian Gardner, chief Washington policy strategist at Stifel, noted that investors are betting on a split Congress. If that materializes, with Democrats achieving their House goals without a so-called "blue wave," he expects a relief rally to follow. Historically, in years when Congress has been divided over the past 13 years, the S&P 500 has delivered an average return of 17%.

Meanwhile, Wall Street is actively hedging against election-driven volatility. Futures tied to the CBOE Volatility Index (VIX) indicate rising demand for protection against S&P 500 swings in early November. Evercore ISI has advised traders to employ a "straddle" strategy on the SPDR S&P 500 ETF Trust (SPY), purchasing both November call and put options at a strike price of $770. This approach allows traders to profit from sharp moves in either direction without making a directional bet. Julian Emanuel, strategist at the firm, noted that the position is attractively priced because VIX remains well below its long-term average despite the broader forces that could trigger significant market shifts. "The risk of surprise events is severely underpriced," he cautioned.

The options market is clearly signaling elevated anxiety, with traders positioning for potential turbulence. Wall Street's line of thinking is straightforward: if different parties control each chamber, the likelihood of aggressive policy changes—whether in AI, defense, or healthcare—diminishes, translating into less uncertainty for markets. Historically, a divided Congress has been a boon for US equities. Data from Carson Investment Research shows that since 1950, under Republican presidents with a split Congress, stocks have averaged annual gains of 13.7%. By comparison, full Republican or Democratic control has yielded average annual returns of 8.3% and 4.9%, respectively, indicating that divided government under a Republican president has been the best performer.

AI has emerged as a defining issue this election cycle, fueled by a rising chorus over data center construction. This has forced investors to confront the growing regulatory risks tied to a technology that has underpinned a four-year bull run in US stocks. Stuart Kaiser, head of US equity trading strategy at Citigroup Inc., wrote in a recent client note that a split government would "force gridlock or compromise," describing it as both the most likely and most positive outcome. In such a scenario, policy choices tend to be moderate, allowing stock markets to refocus on corporate and economic fundamentals. Kaiser has recommended building bullish positions in the S&P 500 or the Invesco QQQ Trust to capitalize on robust tech earnings and benefit from the unwinding of election-related risk premiums. JPMorgan Chase & Co.'s Delta One trading desk has flagged that a divided Congress would create opportunities in stocks tied to the Affordable Care Act, while also favoring traditional defense names, as national security remains a bipartisan priority.

Yet the growing consensus on a divided Congress carries its own danger: if expectations abruptly shift toward a sweep by either party, markets could see sharp volatility. The possibility of Democrats taking both chambers remains real. Although Donald Trump remains the Republican Party's biggest draw, his historically low approval ratings pose a headwind ahead of November. Republicans are hoping a roughly termed "Trumpapalooza" midterm convention will avert a repeat of past losses. Last month, a strategist team led by Michael Hartnett at Bank of America Corp. pointed out that a strong showing for Trump's party, coupled with Greg Abbott's successful reelection in Texas, would be particularly favorable for AI-related stocks. Conversely, Hartnett argued that if Democrats seize the Senate and unseat Abbott, stocks could face a significant downturn. Phil Wool of Rayliant believes a Republican sweep could boost sectors benefiting from further deregulation, singling out energy and financials as potential winners. A "blue wave" Democratic sweep, on the other hand, might lift renewable energy and healthcare providers.

Nevertheless, some view the midterms as little more than a blip on the long-term radar. Omar Aguilar, CEO of Schwab Asset Management, acknowledged that political results always stir client anxiety and uncertainty, but most outcomes have minimal impact on long-term market direction. Certain sectors will see more volatility than others, but over time, these moments present opportunities to rebalance portfolios. "Clients are watching closely, just as they watch $100 oil," Aguilar said. "But does that mean they need to change their strategy? Our advice remains: no, stay the course and ride it out."