A complete guide to the different election scenarios and their likely impact on stocks

Democratic President-elect Joe Biden delivering remarks on Covid-19 at The Queen theater on Oct. 23, 2020 in Wilmington, Delaware and U.S. President Donald Trump addressing supporters during a Make America Great Again rally in Gastonia, North Carolina, Oct. 21, 2020.
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Wall Street firms are finalizing advice to clients on how adjust their portfolios depending on which party controls the White House and the Senate after Tuesday's election.

Though the outcome is anything but certain, strategists say that a reelection for President Donald Trump would on average favor growth stocks while a win for Democrat Joe Biden could be a positive for cyclical value equities.

CNBC reviewed dozens of recent reports published by the largest research firms to distill common takeaways for an investor looking to position themselves ahead of the 2020 election.

Of immediate concern to most of Wall Street's banks was the federal government's ability to pass additional stimulus to help combat the negative economic effects of Covid-19.

Some of the most-recent research came Monday from Wells Fargo equity strategist Christopher Harvey, who wrote that a so-called blue wave could be a short-term positive for markets thanks to increased odds of a larger stimulus package.

Morgan Stanley's Andrew Sheets on Oct. 29 issued forecasts for the S&P 500 based on varying election outcomes.

If Democrats sweep, Sheets sees the index down from Friday's close of 3,269 to 3,100 by Dec. 31, a loss of about 5%. Alternatively, he sees the S&P 500 climbing 3% to 3,375 if Biden wins and Republicans keep control of the Senate.

The strategist sees the S&P 500 rallying 5.5% by year-end to 3,450 if Trump wins and Republicans keep the Senate in a status-quo outcome.

While control of the White House and Senate are widely seen as competitive elections, all of Wall Street's major brokerages believe Democrats will maintain their majority in the House of Representatives.

Differences in leadership style and policy priorities for Biden and Trump are expected to lead to varying market outcomes.