Why Warren supporters will split between Biden and Sanders

The Democratic presidential race is, for all intents and purposes, a two-person affair. Massachusetts Sen. Elizabeth Warren’s departure from the race on Thursday was the end of the line for the one-time front-runner. The big question coming out of Warren’s decision is whether former Vice President Joe Biden or Vermont Sen. Bernie Sanders stands to benefit.

A look at recent data suggests that neither is likely to pick up the clear majority of Warren’s support.

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A new Ipsos/Reuters poll taken after Super Tuesday but before Warren exited the race illustrates the point well. Among all Democrats and independents, Biden led Sanders 40% to 30%, with Warren coming in third with 11%.

When asked about only Biden and Sanders, Biden maintained a 55% to 45% advantage.

This may surprise you, as Sanders seems like a natural home for Warren supporters, given where they stand ideologically. Warren and Sanders had two of the most ideologically left voting records of the candidates in the 2020 presidential race.

Indeed, the exit polls from Super Tuesday reflect that Warren backers were to the left. Her best group ideologically were self-described very liberals. She won 19% of them on Super Tuesday, across states with an exit poll. She took only 6% of moderates or conservatives. Sanders’ ideological curve of backing looked similar. He took 49% of very liberals and 17% of moderates or conservatives.

Biden, of course, is a different cat altogether. He had one of the most moderate congressional records of the different candidates who ran for the Democratic nomination.

Not surprisingly, Biden did his best on Super Tuesday with those in the center. His support rose from 19% among very liberals to 47% among moderates or conservatives.

Ideology isn’t everything, though. A lot more goes into voting during a presidential primary.

For example, Biden and Warren are Democrats. Sanders caucuses with the Democrats in Congress, but he’s an independent.

On Super Tuesday, Biden and Warren did better among self-described Democrats than they did among independents. Biden got 41% among Democrats and 26% among independents. Warren went from 14% with Democrats to 11% with independents.

Sanders, on the other hand, showed the opposite pattern. His support jumped from 25% with Democrats to 34% with independents.

Another issue for Sanders winning over Warren’s voters is their demographics. Warren’s best group throughout this campaign has been white women with a college degree. Across the Super Tuesday contests, she earned 25% of their vote. That’s about double the vote she earned overall and 10 points more than women overall.

One of Sanders’ worst groups this campaign has been white women with college degrees. He came in third with a mere 20% among them on Super Tuesday.

Biden won them with 32% on Super Tuesday. That follows him winning them during his wildly successful South Carolina endeavor. Biden took them with 40%. Like on Super Tuesday, Sanders came in third with 13%.

Obviously, a Warren endorsement of Sanders could change this equation. Biden is currently getting multiple endorsements a day. He’s become the clear choice of party actors, which has historically been highly correlated with doing well in the primaries.

A Warren endorsement of Biden would further his goal of coalescing the party around him.

A Warren endorsement of Sanders, on the other hand, could be a whole other matter. It would suggest that perhaps parts of the party are not ready to crown Biden the nominee and that we are in for a prolonged primary fight.

Unfortunately for Sanders, a Warren endorsement doesn’t seem to be coming anytime in the immediate future.

For now, Biden is likely to maintain his newfound national advantage over Sanders, even with Warren out of the race.