Final answer:
The Democratic Party's relatively low level of factional infighting is influenced by increased political polarization, resulting in more ideologically aligned party members. Institutional factors such as the Electoral College and a general societal trend towards unity also reduce the likelihood of supporting dissenting factions leading to significant infighting.
Step-by-step explanation:
The question regarding why is there relatively little factional infighting in the current Democratic Party can be understood by examining the structure of political parties in the United States and the prevailing trends. Historically, both the Democratic and Republican parties have sought to represent a wide range of voters, including moderates, often competing for the middle ground to win elections. However, since the 1990s, the parties, including the Democratic Party, have experienced a rise in polarization, which has led to a reduction in moderate members and an increase in party cohesion among more ideologically aligned members. This ideological alignment has reduced the instance of factional disputes within the party.
Factional competition has been more prevalent historically in a single-party dominant system, which is not the current national landscape of the U.S. politics. Furthermore, the past several decades have seen an increase in divided government, affecting both parties' approaches to collaboration and compromise, with the electorate often sending a president a Congress of the opposing party.
The increasing ideological divergence has, on one hand, contributed to clearer distinctions between the parties, enabling voters to make more informed choices. On the other hand, it has also contributed to a decline in bipartisan cooperation. The Democratic Party's relative internal cohesion may currently be influenced by this broader national trend towards polarization, alongside mechanisms like the Electoral College and the general prosperity and unity in the United States, which discourages large dissenting factions that might otherwise lead to significant factional infighting.