Dow scores its best day in 18 months in a broad relief rally after Democrats sweep to power in Congress

Stocks surged Wednesday, with the Dow recording its best single-day performance in 18 months, as investors reacted to Democrats securing control of Congress. The rally was broad-based, spanning equities, while oil prices fell sharply and bond yields declined. Market participants linked the moves to optimism that a quicker end to the Iran war may now be possible with the new congressional leadership in place.

The reaction reflects how markets price geopolitical risk. Lower oil prices suggest traders expect reduced supply disruption if the conflict winds down sooner, while falling bond yields point to shifting expectations around inflation and growth. Equity gains across sectors indicate the optimism was not confined to energy-sensitive names.

What to watch: whether policy signals from the new Congress match the market's expectations, and whether oil's decline holds as the situation develops. Investors should note that relief rallies tied to geopolitical headlines can be volatile, and the durability of these moves will depend on concrete developments rather than sentiment alone.