Approval Voting Unmasks Consensus Opinion in the California Primary

The passing of Dianne Feinstein has opened the door to one of the most contentious Senate primaries in California’s recent political history. Candidates of all political stripes are vying for the seat, with more than 20 on the ballot for the first round in March. Unlike most states, California’s blanket primary system makes the contest even more compelling. Under the system, Democrats, Republicans, Independents, and third-party candidates are all thrown into the same contest, the two candidates with the most support advance to a runoff. With so many candidates running, this contest is a perfect example of a broken election impacted by vote-splitting. As the election nears, will the results reflect the wishes of the electorate? 

What is Vote-splitting, and how does Approval Voting Address it?

Vote-splitting is common in crowded elections that use “choose-one” plurality voting. It happens when like-minded or similar candidates split the vote, and a candidate who doesn’t reflect the majority wins. Oftentimes, vote-splitting distorts the will of the electorate. In 2022, a vote-split election occurred in 30 percent of the congressional primaries, and in over 500 state legislative districts nationwide. These contests included some of the most competitive districts, which impacted who controls our government. 

Approval voting addresses vote-splitting by allowing voters to “hedge their bets” and pick all the candidates they like. With a simple change, we ensure that the winner of an election will have the highest level of support. Unlike other alternative methods, the results are tabulated using simple addition, and the candidate with the most support wins. Currently, two jurisdictions use approval voting: Fargo, ND, and St. Louis, MO.

How Would Approval Voting Change the California Senate Race?

As we all know, California is a state dominated by the Democrats at the statewide level, and a Democrat will likely win this seat. However, will the primary with 20+ candidates yield the runoff that people want? The answer to that question is harder to predict. Three high-profile Democrats from the congressional delegation entered the contest in the early stages: Rep. Adam Schiff, Rep. Barbara Lee, and Rep. Katie Porter. On the Republican side, Eric Early and the late entry of former baseball player, Steve Garvey increased the likelihood that voter support will be widely dispersed in the first round. Will a vote like this, using choose-one voting, capture what the voters want? 

Working alongside our partners at SurveyUSA, The Center for Election Science commissioned a comparative poll to measure the impact of the voting method on the result. Our poll tested public support for the candidates using plurality versus the support under approval voting. According to our poll, the election results would look very different depending on the voting method. 

As you can see from the graph, the general election runoff would include different candidates based on the voting method used. Under the typical choose-one system, an extreme vote-split produces a runoff between Democrat Adam Schiff and Republican Steve Garvey, who advances to the runoff with just 15% support. 

In the approval voting simulation, we see that all three top-tier Democrats surpass Garvey, and the runoff would be between two Democrats, Rep. Adam Schiff, and Rep. Katie Porter. Unsurprisingly, the approval voting poll unmasks the consensus opinion that Californians want a Democrat in the seat. From a political perspective, we see that approval voting would produce a result that more closely reflects the political bend of the state. Even though no candidate achieves a majority, we see that a good position of our respondents would support more than one candidate if given the chance.

Battle for the Bay

Approval voting gives us a clearer picture of the regional support for each candidate, and how approval voting could change the race’s complexion. 

Rep. Adam Schiff enjoys a strong statewide advantage over his rivals, amassing significant support in northern and southern California. Approval voting clarifies this consensus, as he significantly closes the gap between him and Rep. Lee in the Bay Area under that method. Under plurality voting, Rep. Barabara Lee enjoys an 8-point advantage in the Bay area. Her congressional district falls within that region, so one should expect strong support for her candidacy. However, Bay Area voters also appear very open to supporting Rep. Schiff, as Lee’s regional advantage drops to just 4-points under approval voting. One potential reason for Rep. Schiff’s statewide advantage is his strong approval among self-described liberals (65%) and voters with a post-graduate degree (50%), which bolsters him in the Bay Area.

L.A Voters Stay Local

While Rep. Schiff has made inroads in the Bay Area, Greater Los Angeles voters appear to be sticking with local candidates. Under plurality, Schiff (19%) and Republican Steve Garvey (15%) are in the lead, with Rep. Katie Porter close behind (13%). But this is where approval voting makes a big difference, because these plurality results don’t accurately reflect the electorate.

When given more choice with approval voting, we see that Rep. Schiff and Rep. Porter have more local support than Garvey. Garvey drops to third place under approval voting and barely outpaces Rep. Lee. Unfortunately for Lee, she has not been able to match Schiff’s cross-geographical appeal.

Ultimately, approval voting shows that when L.A. voters aren’t forced to split their vote, they want a Democrat in office. 

Capturing the Power of Key Voting Blocs

Crowded elections can disperse the power of influential voting blocks. Since 2016, educational attainment has become one of the most important blocs for the Democrats. Under plurality, the power of voting blocs is often split, as like-minded voters divide among similar candidates.

However, our poll shows approval voting allows a consolidation of support and consensus to a greater degree. As the graph shows, voters with a college or postgraduate degree are split among the top four candidates under plurality voting. But with approval voting, we see a clear consensus emerge among both populations around the Democratic candidates. Approval voting has the power to consolidate and expand the power of key voting blocs in any jurisdiction. 

The choose-one blanket primary in March will force Californians to vote strategically, potentially robbing them of their ability to vote for their true favorite. Approval voting can change that, while incentivizing candidates to engage with a broader swath of voters. Everyone deserves an equal voice with their ballot.

For a closer look at our poll results, including crosstabs, click here.

Reimagining Elections Series #1
This year, CES will be dissecting how approval voting would impact real-world contested races in the “Reimagining Elections Series.” Stay tuned for more entries to come!