Here's the most important news, trends and analysis that investors need to start their trading day:
1. Dow set to add to Tuesday's record close
The Dow was set to open higher Wednesday, one day after the 30-stock average closed at a record high. The S&P 500 and Nasdaq on Tuesday also closed at records on optimism around Pfizer's vaccine rollout in the U.K. and coronavirus stimulus talks in Washington.
The S&P 500 saw its first close over 3,700 as Wall Street has gotten off to a strong start in December in a continuation of November's rally. So far this year, which included a monumental plunge to coronavirus lows in March, the Dow was up 5.7%; the S&P 500 was up nearly 14.6%; and the Nasdaq was up over 40% — particularly powered by tech stocks, which have been beneficiaries of the stay-at-home economy during the pandemic.
2. DoorDash set to begin trading in wave of tech IPOs
DoorDash is set to debut on the New York Stock Exchange on Wednesday. The U.S. food delivery company Tuesday evening priced its initial public offering at $102 per share, above the revised target range of $90 to $95. The offering gives DoorDash a value of about $38 billion. DoorDash is the first IPO in a late-year consumer technology wave that includes the expected debut of Airbnb on Thursday.
Online stock trading app Robinhood, which is favored by younger investors and has seen newfound popularity during the pandemic, picked Goldman Sachs to lead preparations for an IPO, people familiar with the matter told Reuters. The offering could come next year with a value of more than $20 billion.
3. Trump administration makes $916 billion offer in stimulus talks
The Trump administration jumped back into Capitol Hill talks on new Covid-19 stimulus. Treasury Secretary Steven Mnuchin made a $916 billion offer to House Speaker Nancy Pelosi late Tuesday. The California Democrat said the White House plan includes direct payments to Americans but eliminates a $300 per week federal unemployment benefit boost supported by bipartisan negotiators working to refine a $908 billion framework released last week.
Senate Majority Leader Mitch McConnell on Tuesday recommended putting aside legal protection for businesses from Covid lawsuits and state and local government funding roadblocks and pass a bill that includes the areas of agreement. The Kentucky Republican said the tougher issues can be handled after the new year.
4. Vaccine developments dominate headlines from the UK to the UAE
People who have a history of "significant" allergic reactions should not receive the coronavirus vaccine developed by Pfizer and BioNTech, U.K. drug regulators said Wednesday. The U.K., which started its mass vaccination drive Tuesday, became the first country to approve the Pfizer vaccine.
As the FDA gets ready to meet Thursday on Pfizer's emergency use application and Moderna's next week, United Arab Emirates health authorities said data from human trials there of a Chinese vaccine showed 86% efficacy. It's unclear on how that rate was calculated. The UAE in July began Phase 3 human trials of the experimental vaccine, which was then approved for health workers there in September.
The coronavirus vaccine developed by AstraZeneca and the University of Oxford has become the first to have its late-stage trial results independently reviewed and published in a peer-reviewed medical journal. The study, published Tuesday in The Lancet, confirmed an average effectiveness of 70%. It also confirmed 62% efficacy for two full doses and 90% efficacy for the half-dose and then full-dose regimen.
5. Supreme Court rejects GOP bid to reverse Biden's win in Pennsylvania
The Supreme Court denied a request by Republicans to reverse President-elect Joe Biden's victory in Pennsylvania. The top court rejected a petition from Trump ally Rep. Mike Kelly. The Pennsylvania Republican lawmaker argued that virtually all of the state's mail-in ballots were unlawful. The action closes off one of President Donald Trump's last remaining paths to overturning the results of the 2020 election in court, even as some far-fetched legal cases remain in the works.
Republican Texas Attorney General Ken Paxton filed a lawsuit directly to the Supreme Court, seeking to invalidate presidential election results in four swing states that helped secure Biden's victory over Trump. The suit, which legal experts quickly dismissed as political theater, claimed "unlawful election results" in Pennsylvania, Georgia, Wisconsin and Michigan.
— The Associated Press contributed to this report. Follow all the developments on Wall Street in real time with CNBC Pro's live markets blog. Get the latest on the pandemic with our coronavirus blog.