Investing.com -- A Republican sweep in the recent U.S. election would likely boost the S&P 500 more than a split Congress, according to RBC Capital analysts.
The bank said in a note Thursday that historically, S&P 500 returns have averaged 13% in years following a Republican sweep, compared to only 5% with a Republican president and a divided Congress, making the sweep scenario "more favorable" for U.S. equities.
"In light of both the historical playbook and this policy thought, a Republican sweep seems more favorable to US equities at the moment," RBC analysts noted.
With Republicans poised to control both the presidency and Congress, RBC believes Trump would have an easier path to pass his tax agenda, a likely catalyst for the broader stock market.
Tax cuts, as seen in Trump's first term, are expected to be a priority over trade tariffs in a full Republican government, potentially fostering a more favorable environment for sectors like energy and financials.
RBC explained that "Trump might be more likely to prioritize his tax agenda over tariffs" in a sweep, which should be a net positive for corporate profits and investor sentiment.
Beyond taxes, RBC analysts pointed to alleviated uncertainty around the political landscape as another reason for a possible S&P 500 rally.
They believe global investors may increasingly overweight U.S. equities under a Republican-led administration, as regulatory rollbacks and pro-growth policies likely accelerate business activity.
However, they add that some headwinds remain. RBC flagged Trump's stance on tariffs, particularly those aimed at China, which could fuel inflationary pressures and possibly dampen consumer spending.
Another concern is rising interest rates: if 10-year yields climb sharply beyond 250 basis points, RBC warned that "equity valuations seem likely to eventually take a hit."
Additionally, a strong U.S. dollar, which often follows Republican wins, could weigh on S&P 500 earnings by impacting overseas revenue streams.