The U.S. stock market closed higher on Monday, with all three major indices posting gains. The S&P 500 rose 1.18%, the Nasdaq Composite gained 2.07%, and the Dow Jones Industrial Average climbed 0.59%. The broad-based rally was driven by a temporary halt in hostilities between the U.S. and Iran, which provided a brief respite from geopolitical tensions. Additionally, the "Magnificent Seven" tech stocks, including Alphabet and Google, saw gains as they continued to recover from last week's sell-off. Comcast's stock surged on news of a potential split, further contributing to the positive sentiment.

The market's tone was decidedly risk-on, with investors taking advantage of the temporary easing of geopolitical risks. Tech stocks, particularly those in the "Magnificent Seven," benefited from a rebound, while Comcast's announcement of a potential split added to the positive momentum. However, the market's performance was somewhat mixed, with some stocks struggling after the OpenAI IPO blow. Despite this, the overall sentiment remained bullish, with the Dow set to finish above 52,000 for the first time. The rally was broad-based, with all three indices posting gains, indicating a widespread optimism in the market.