Former Vice President Joe Biden's impressive victory on Tuesday in Michigan's Democratic presidential primary appeared even more sweeping on Wednesday, showing he won every county in the state over U.S. Sen. Bernie Sanders of Vermont.

That was especially surprising given that Sanders won all but 10 of Michigan's 83 counties four years ago in a surprise upset of the eventual Democratic nominee, Hillary Clinton, that helped establish him as a viable candidate on the national stage.

It was a shocking turn of events for Sanders, with the self-described democratic socialist becoming the victim of a Democratic electorate that, regardless of race and geographic setting, decided that his radical views for reshaping government weren't what was needed in defeating President Donald Trump in the fall.

"What's become even clearer in the past week: Democratic voters don't want a protracted primary fight," tweeted David Wasserman, a political analyst with the Cook Political Report, a political handicapping service in Washington, D.C.

Sanders seemed to acknowledge that on Wednesday when he indicated he was staying in the race for now even though he knows he is losing, arguing that Americans support ideas such as Medicare for All and free tuition for colleges but believe Biden is the more electable candidate in a campaign against Trump.

"We are losing the debate over electability," he said, while promising to fight on as a way to try to push Biden toward his positions.

Four years ago, Sanders stunned Michigan and the nation by upsetting Clinton in the state, despite her having what appeared to be a double-digit lead in the polls.

This year, Biden went into the election with a similar polling lead. But this time, the favorite won handily, 53%-36%, or by about 262,000 votes statewide, according to the Associated Press' count.

The count was still being finalized but it appeared Biden won most of the state's 125 delegates toward the Democratic nomination, taking 72 to Sanders' 52 as of Wednesday, according to RealClearPolitics.com, a political tracking website.

Exit polls pointed to a big Biden win

The Free Press and other media outlets called the race for Biden shortly after polls in the western Upper Peninsula in the Central time zone closed at 9 p.m. Tuesday. By then, Biden had staked out a strong-enough lead to make a firm projection in his favor.

Exit polls of voters leaving polling places showed why.

According to exit poll results posted on CNN's website, the former vice president led among men 47%-43% and women 58%-35%, as well as white voters, 51%-40%, and black voters, 66%-27%.

Four years ago, the results were much different as Sanders led with men, 55%-44%, and whites, 56%-42%.

More:Joe Biden wins Michigan Democratic primary

More:Michigan primary 2020: Live results for presidential vote, plus metro Detroit races

As expected, Sanders maintained a lead among younger voters, winning those ages 18-29 by a margin of 76% to Biden's 19%. But they made up just 16% of the electorate, according to the exit polls and Biden did far better among the larger group of older voters this year.

Where Sanders won 62%-32% among the 38% of voters under the age of 45, Biden won voters over that age 65%-24%. And those older voters made up nearly two-thirds of the electorate this time, compared with just over half in 2016.

Metro Detroit points the way to Biden's win

Much was made in 2016 as Clinton lost in Michigan to the fact that she did so while winning in Michigan's largest area, metro Detroit.

It was an unusual outcome, given that Wayne, Oakland and Macomb counties are the state's single-largest geographical voting bloc and they often, though not always, vote in the same general political direction.

This year, according to the most recent data from the Michigan Secretary of State's Office, Biden won 54% of the overall vote in Wayne, Oakland and Macomb counties, which was actually 1% less than that posted by Clinton four years ago.

But Biden did so while Sanders' total percentage in those counties fell from 43% to 35%, as there were more names on the ballot of a dozen candidates who have already dropped out of the race.

And Biden's percentage in those counties was worth far more to his statewide total: With 152,991 more people in the three counties voting in the Democratic primary this year, an increase of 28%, Biden got more than 78,000 more votes out of metro Detroit than Clinton did.

It's also worth noting that the increase in Democratic turnout was especially big in metro Detroit's two suburban counties, increasing more than 32,000 votes, or 33%, in Macomb, compared with four years ago, and nearly 80,000 votes, or 44%, in Oakland County. If Democratic turnout in those counties follows the same pattern in the fall, it could mean big trouble for Trump.

Support in the rest of the state never appeared for Sanders

Most stunning, however, was how voters across the state picked Biden over Sanders, given how they voted four years ago

In 2016, Sanders beat Clinton by 56% to 42% outside of metro Detroit, which allowed him to overcome her advantage there.

In 2020, Biden beat Sanders 52%-38% outside of metro Detroit, a huge turnaround for a candidate Democrats in those areas had previously endorsed with their vote.

That included a handful of key counties that are traditionally Republican but, in some cases, have been trending more Democratic in recent elections. In 2016, Sanders won handily, for instance, in Kent and Ottawa counties in west Michigan, in Livingston County in the Detroit exurbs and in Grand Traverse County in northern Michigan with close to 60% of the vote or better.

He lost them all to Biden this year, and in all but Kent, by decisive margins. Sanders lost by more than 9% in Grand Traverse, 12% in Ottawa and 17% in Livingston. In Kent, Biden won by a slim margin, slightly more than 1% of the vote, but four years ago, Sanders won there by almost 25 percentage points.

Perhaps even more stunning, Sanders lost in what was seen as his base of big college counties, being defeated by slim margins in Washtenaw, where the University of Michigan's Ann Arbor campus and Eastern Michigan University are located; Ingham, where Michigan State University is located in East Lansing, and Kalamazoo County, where Western Michigan University is located in Kalamazoo.

Four years ago, Sanders' win in Michigan raised the hopes of his supporters immensely. In the days leading up to this year's primary, he barnstormed the state with rallies in Detroit, Grand Rapids, Dearborn and Ann Arbor, clearly understanding that if he lost a state that helped send Trump to the White House — and is expected to be a battleground in the fall election — it could doom his campaign.

"Sanders gambled on Michigan," Amelia Thomson-DeVeaux, a senior writer with the political analysis website FiveThirtyEight.com, wrote early Wednesday morning. "He traveled all over the state in the days leading up to the primary. ... I keep going back to what I heard from Michigan voters over the past few days — a sense of primary fatigue, alarm over the fighting among the candidates as the contest got heated and a desire to start gearing up for the battle against Trump."

"Plenty of voters admitted that Biden wasn’t their first choice," she continued, "but they seemed more than happy with him as their candidate. And that, I think, will make it hard for Sanders to keep fighting."

Contact Todd Spangler:tspangler@freepress.com. Follow him on Twitter@tsspangler. Read more onMichigan politics and sign up for ourelections newsletter.