Former Vice President Joe Biden now has a nearly insurmountable delegate lead on Sen. Bernie Sanders, making him the prohibitive frontrunner for the Democratic presidential nomination. On Tuesday, he trounced Sanders in delegate-rich Florida, defeating the Vermont senator by nearly 40 percentage points. That win was quickly bolstered by double-digit victories in Illinois and Arizona.

And yet, a pattern has emerged in Democratic primaries. Biden keeps winning, but most Democrats embrace an idea closely associated with Sanders: Medicare-for-all.

Take Florida, where Biden soundly defeated Sanders, winning 62 percent of the vote to the senator’s 23 percent. It was Biden’s biggest win of the day, and one of his strongest showings in the primary so far, but even there, 55 percent of primary voters said they support “a government plan for all instead of private insurance,” as compared to the 33 percent who opposed such a shift. In Illinois and Arizona, Biden won smaller-but-still-commanding victories. Yet 61 percent of Illinois primary voters and 58 percent of Arizona primary voters prefer a government plan to the current system.

So what’s going on?

After this trend of many Biden voters seeming to support Sanders’s health proposal emerged in Super Tuesday exit polls early this month, my colleague Dylan Scott took a deep dive into what the polling data says about Democratic voters and health policy. Among other things, he found that most Democrats support expanding the government’s role in ensuring that all Americans have access to health care, but they don’t have particularly strong preferences between Biden and Sanders’s proposals for doing so.

Although his plan doesn’t go as far as Sanders’s, Biden also advocates for health care reform. Biden’s alternative to Medicare-for-all, a “public option” health care plan that would be available for free to many low-income Americans — and that many other Americans could buy into if they chose — is also very popular. According to a Kaiser Family Foundation poll, 62 percent of Democratic voters support both Sanders’s Medicare-for-all plan and Biden’s public option proposal.

Additionally, many Democrats appear to have settled on the view that Biden is more likely to prevail in November than Sanders, and a large chunk of Democratic voters view electability as the single most important factor driving their primary vote. As Scott writes, “not everybody is sold on Sanders as the right messenger against Trump. The data is mixed on whether Medicare-for-all would hurt or help Sanders against the president — it may just be a wash — but many Democratic voters believe (rightly or wrongly) Biden would be more viable than the Vermont senator.”

So, while the heart of the Democratic Party is with Sanders on the Vermont senator’s signature proposal, they are less convinced that Sanders is the right standard bearer for the party as a whole. Barring extraordinary events, Biden now enjoys such a commanding lead in the race to become the Democratic candidate that it is hard to imagine Sanders emerging as the party’s nominee.