With the Michigan primary, all suspense about the presidential race disappeared; the Republican ticket will consist of Donald Trump and Mike Pence; the Democratic ticket, Joe Biden and a player to be named later.

Maine progressives are especially disappointed. Though the combined vote totals on March 3 for Bernie Sanders and Elizabeth Warren exceeded that for Biden and Michael Bloomberg, Biden won here too, on his way to inevitability. Yet there’s another race still to be run.

Normally, the selection of a vice president is only a parlor game for party insiders. But these are not normal times. Biden’s VP choice could mean the difference between yet another nail-biter, and – possibly – a Democratic landslide.

Almost without our noticing it, the office of vice president has changed dramatically, as Joel K. Goldstein chronicles in his 2016 book, “The White House Vice Presidency: The Path to Significance, Mondale to Biden.”

It was Walter Mondale’s vice presidency that set the pattern. Mondale, an old-line liberal senator from Minnesota, lent valuable credibility to former one-term Georgia governor, Jimmy Carter.

Carter, recognizing Mondale’s contributions, offered him his pick of White House offices. Vice presidents had previously been exiled to the Old Executive Building.

Mondale chose a spot, right next to the Oval Office, originally slated for the chief of staff. Mondale served Carter capably and well, a partner who never embarrassed the boss. Since then, not every vice president has had the same presidential relationship, but each has stayed in the White House.

There can be a dark side to a strong vice president, admittedly. During George W. Bush’s first term, Goldstein writes, there were credible reports that Dick Cheney was having a greater effect on policy than Bush, especially when it came to tax cuts, torture and the war in Iraq.

The Democratic record on vice presidents isn’t a great deal better, for different reasons. Since Mondale, running mates have ranged from middle-of-the-pack to dismal. None showed real presidential ability, though one – Biden – might still have that chance.

Other than a capable partner, the imperative is keeping the party together, and here Democrats have done even worse. No one expected Hillary Clinton to pick Bernie Sanders in 2016, but choosing very junior Virginia Sen. Tim Kaine did nothing for the ticket and was another factor in her loss to Trump.

Biden’s running mate will probably be a woman. Given women’s strong majority among Democratic voters, and recent electoral success, it could hardly be otherwise.

Given his middle-of-the-roadness, Biden will incline toward two primary rivals, Sens. Amy Klobuchar or Kamala Harris. Neither would challenge Biden’s tepid policy proposals or his propensity for playing it safe.

That approach won’t work. Issues that really matter to restive young Democrats – mammoth income inequality, global warming, and the crushing consumer costs of college and health care – won’t be solved by nibbling around the edges.

If Joe Biden wants to be a successful president, he must leave his comfort zone, and unite his party. He can’t do that with Klobuchar or Harris.

The last candidate who, by himself, might have united the party was Maine’s Ed Muskie, in 1972 the early frontrunner against Richard Nixon. As hatchet man Pat Buchanan wrote to Nixon, “If Mr. Muskie is not cut and bleeding before he goes into New Hampshire, he will very likely to do massively well there . . . Muskie is ideally situated to unite the warring factions of his party, and if they are united, that is bad news for us.”

What’s now known as Watergate began with Nixon’s secret attacks against Muskie, and – by the time Muskie arrived in New Hampshire – he was already reeling.

Joe Biden can’t unite Democrats now, but he can reach across the ideological divide and win the votes of progressives he badly needs. He can name Elizabeth Warren.

Warren’s own campaign disappointed many. She wandered off-message in trying to adopt “Medicare for All” as her own; economic and budget issues are her true strength. Still, Warren would be the most qualified vice presidential nominee Democrats have had since Mondale, and she comes with a national following.

The logic of a Warren choice is overwhelming, but it will take a concerted campaign to convince Biden he has to make it. Progressives can make this their new cause, along with moderate women who rightly feel that – once again – they didn’t get a fair shot at the top spot.

Since the Republic was founded, every president has been a man – and so has every vice president. For a woman to get to the top, it may be that the vice presidency is just the ticket.

Douglas Rooks, a Maine editor, reporter, opinion writer and author for 35 years, has published books about George Mitchell, and the Maine Democratic Party. He welcomes comment at drooks@tds.net

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