Bank of America's historical analysis supports the case for staying invested through the midterm vote, which could encourage buying on any pre-election weakness in US equities. Strong fourth-quarter seasonality adds to the constructive backdrop just as the S&P 500 trades near records. The bigger risk lies outside politics: with Treasury yields at multi-decade highs and oil supply still fragile, rate and energy shocks could overwhelm any seasonal tailwind. Greater clarity on fiscal policy after the vote may also matter for bond markets, where concern over government borrowing is already lifting yields.---Midterm years are supposed to be tough for stocks, but 2026 hasn't read the script, and Bank of America says the best part of the cycle may still be ahead.Summary:The S&P 500 is up 13% this year, against an average of around 3% in midterm years, per Bank of America citing Bloomberg data.That puts 2026 on course for the best midterm year for US stocks since 2006.Since WWII, the index has risen in every six- and 12-month period after a midterm, by an average of about 13% and 14%.The fourth quarter has averaged gains of around 5.6% since 1930, the strongest stretch of the year.Bank of America says long-term returns depend more on earnings, valuations, jobs and investment than on election results.US stocks are breaking with the usual pattern of a midterm election year, and history suggests the period after the vote has tended to be even better for equities, according to analysts at Bank of America.The S&P 500 had gained 13% this year as of late September, the bank noted, citing Bloomberg data. That compares with an average return of around 3% in midterm years and puts 2026 on track to be the best such year for US equities since 2006. Bank of America said the outperformance shows that each election cycle plays out differently, and that historical patterns are best used as a guide for handling volatility rather than as a forecast.The bank sees the outlook after November's vote as increasingly supportive. Since the Second World War, the S&P 500 has risen in every six-month and 12-month period following a midterm election, with average gains of about 13% and 14% respectively. Over a shorter three-month window, the index has finished higher nine times out of ten.Seasonality has also tended to work in investors' favour late in election years. The fourth quarter has historically been the strongest stretch of the year, with average gains of around 5.6% since 1930, well ahead of the first three quarters. October has been a positive month about two-thirds of the time. Bank of America added that clearer direction on US fiscal policy once the election is settled could provide further support.The analysts acknowledged that market swings tend to increase in midterm years, but said selling in response to short-term political uncertainty has seldom paid off for long-term investors. Over longer periods, they argued, stock returns and economic performance depend far more on corporate earnings, valuations, the jobs market and business investment than on which party wins.That framing may be tested this year. Equities are rallying alongside US Treasury yields at their highest levels in almost two decades, a combination some strategists warn leaves stocks vulnerable if borrowing costs keep climbing. Historical election patterns offer encouragement, but they will matter less than whether earnings growth can keep pace with a higher cost of capital. This article was written by Eamonn Sheridan at investinglive.com.