No one disagrees that the United States is very polarized despite the Democrats controlling all major elected branches of the federal government. However, their margins are very thin as Biden's win in the swing states came down to around a 100,000 votes, and the Senate is at a 50-50 with VP Harris casting the tie-breaking vote. Even in the House, Democrats lost seats in the last election and based on historical precedent and early polling, they look likely to lose control in the 2022 midterms.
In such a close and polarized electorate, small incidents can have massive ripple effects. Think of the potential impact of Pfizer's
During President Barack Obama's term, Justice Antonin Scalia passed away, and his choice as a replacement - Merrick Garland - was blocked by Senate Majority Leader Mitch McConnell with his replacement - Justice Neil Gorsuch - chosen by President Trump. Then, Justice Ginsburg passed away during President Trump's term, and he was able to select her replacement - Justice Amy Coney Barrett to give conservatives a very decisive 6-3 edge on the Supreme Court.
The latest event which could have big implications is the California recall election. Despite the state leaning Democratic, there is some momentum for the recall to be successful given that some on the left are unhappy with Governor Gavin Newsom and conservatives are in favor of the recall. Additionally, the Democrats have not unified behind a single candidate, so if the recall is successful, it's likely that a conservative - Larry Elder - could become the state's governor.
This could have ramifications in the Senate as California's senior senator, Dianne Feinstein is 88 years old, and there have been reports of health problems. If Elder becomes governor, then he would pick Feinstein's replacement which would tilt the body to Republican control which could effectively block the rest of President Biden's agenda which is essentially what happened during the last 6 years of President Obama's tenure.
The one silver lining for Democrats is that recent polling seems to indicate that momentum is on Newsom's side in terms of public polling and ballots returned by party choice. However, the last two elections have consistently underestimated Republican strength, so both sides shouldn't rest easy until the final results are tabulated.