The 21st Senate District falls within the boundaries of Los Angeles County and San Bernardino County. Scott Wilk (R) is the incumbent and has held the seat since 2016.
This district shows the following party registration for the three largest political groups (the source is http://www.l2political.com):
This is a competitive seat that could see either party win. We saw four candidates run for the open seat in 2016. Here are the 2016 primary results:
Johnathon Levar Ervin (D)- 33.7%
Steve Hill (D)- 11.9%
Star Moffatt (R)- 7.7%
Scott Wilk (R)- 46.7%
148,655 ballots were cast in this race. 54.4% of the vote went to a Democrat and 45.6% of the vote went to a Republican. When compared to November, Wilk snuck out a victory over Ervin by a total of 52.8% vs. 47.2%.
The margin from 2016 is close enough that we could see a seat like this flip, depending on the voter turnout model.
In 2020 we saw four Democrats run in the primary, likely smelling blood in the water. Here are the results from the March 3 2020 election:
Warren Heaton (D)- 10.1%
Steve Hill (D)- 6.0%
Dana LaMon (D)- 12.0%
Kipp Mueller (D)- 18.8%
Scott Wilk (R)- 53.2%
179,710 ballots were cast in this race. We saw the Republican get 53.2% of the vote (Compared to 54.4% in 2016) and Democrats combine for 46.8% of the vote (Compared to 45.6% in 2018). These numbers also need to weigh the fact that a competitive Democratic primary was driving up turnout for Democrats.
My prediction is that NPP voters lean very conservative in this district. I predict that Scott Wilk is going to win re-election in a very close race.