Monday was a solid day for the stock market, as investors generally reacted favorably to news that lawmakers had reached a compromise to end the government shutdown that had extended throughout the weekend. Major benchmarks rose further into record territory, with the Dow and broader indexes seeing gains of 0.5% to 1%. Helping to lift overall sentiment was good news from earnings season, as well as on the mergers and acquisitions front. Wynn Resorts (WYNN -0.03%), Juno Therapeutics (JUNO), and FirstEnergy (FE -0.90%) were among the best performers on the day. Below, we'll look more closely at these stocks to tell you why they did so well.

Wynn wins

Shares of Wynn Resorts climbed nearly 9% after the casino giant reported its fourth-quarter financial results. The company said that revenue climbed 30% from the year-earlier period, with massive gains coming from Wynn's properties in Macau, including the news Wynn Palace resort. Adjusted earnings nearly tripled from what Wynn brought in 12 months ago, and the casino company also said that it reaped a $340 million tax benefit as a result of reductions in corporate tax rates. Coming off a great 2017, Wynn Resorts is putting itself in even better position to prosper from favorable conditions in 2018.

Juno makes its deal final

Juno Therapeutics stock soared another 27%, adding to its gains from last week after investors got confirmation that Celgene (CELG) will buy the biotech company. Speculation had swirled around the two last week, but today's announced deal set specific terms for the $9 billion deal, which values Juno at $87 per share. For Celgene, the move expands its exposure to immunotherapy, which has been an extremely interesting area in biotech lately, and adds to its pipeline of treatments. For Juno, what's most surprising about the news is that it got such a high price, given that the stock had jumped over 50% when rumors of a deal were first reported last week. In the end, Celgene will pay almost double what Juno shares fetched early last week, leading some to think it overpaid.

FirstEnergy gets some activist interest

Finally, shares of FirstEnergy picked up more than 10%. The utility company said that it would accept $2.5 billion in cash from a group of investors that includes activist investment company Elliott Management in exchange for newly issued preferred and common stock. The preferred issue is a mandatory convertible, which means that the holder will have to convert at a price of roughly $27.50 per share at expiration. What has investors excited is that FirstEnergy will also respond to activist investor calls to make strategic changes, with the hope of exiting the competitive electricity generation industry expeditiously. That will make FirstEnergy a focused regulated utility, potentially making it less volatile and ensuring stability for the foreseeable future.