This is the latest in a series where I make the best case for each of Joe Biden’s possible vice-presidential candidates. The other pieces can be found here.

In presidential elections, winning isn’t everything. It’s the only thing. Presumptive Democratic nominee Joe Biden can spend all day in his basement designing a fantasy platform, imagining his ideal Cabinet and drafting soaring speeches to heal our political divides — but it’ll all be for nothing if he fails to get 270 electoral votes.

That makes Biden’s equation for picking a running mate simple: He needs a qualified candidate who can help him win a key swing state such as Florida, Michigan, Pennsylvania or Wisconsin. Every other consideration — age, ideological fit, working relationship — should take a back seat to this straightforward election math. And according to those numbers, Wisconsin Sen. Tammy Baldwin is the right, and arguably the only, choice.

Baldwin is obviously qualified: She’s been in the Senate since 2013 and was in the House for 14 years before that. She’d make history as the fourth woman — and the first out lesbian — on a presidential ticket for a major party. And, as a progressive, she’d bring ideological balance to the ticket.

But most important, she’s from Wisconsin: the state that gave Trump his 270th electoral vote in 2016. If Baldwin brought Biden a mere two points in Wisconsin, that would be a huge help.

And Biden doesn’t have any other options like Baldwin in the swing states.

The Fix’s Aaron Blake analyzes whom former vice president and presumptive Democratic presidential nominee Joe Biden might pick as his running mate in 2020. (The Washington Post)

In Florida, both senators and the governor are Republicans, and Biden probably should stick to politicians who have shown they can win a marquee statewide race. Biden has also pledged to pick a woman as his vice president, so Pennsylvania Gov. Tom Wolf and Pennsylvania Sen. Robert P. Casey Jr. are out.

Biden has two options in Michigan — Sen. Debbie Stabenow and Gov. Gretchen Whitmer — but neither would be a stronger addition to the ticket than Baldwin. Stabenow doesn’t look like a good bet right now: She underperformed expectations in 2018, when she beat Republican challenger John James by only 6.5 points, while Baldwin won her latest race by double digits. Whitmer is a gamble, too. By the end of the novel coronavirus crisis, she could be wildly popular or completely toxic in her home state, depending on how the Trump-stoked protests against her social distancing orders play out.

There’s also Arizona Sen. Kyrsten Sinema, who would make history as the first openly bisexual candidate, and might even be to the right of Biden. But Baldwin has more Senate experience than Sinema, and Wisconsin is still a touch more purple than Arizona.

Baldwin is simply head and shoulders above the other contenders. She’d give Biden a boost where he needs it, and she would avoid the pitfalls of similar candidates, though she has some weaknesses, too.

Baldwin hasn’t run for president, so she doesn’t have as much experience in the national spotlight as Massachusetts Sen. Elizabeth Warren, Minnesota Sen. Amy Klobuchar or California Sen. Kamala D. Harris. And if she left her Senate seat, Republicans would have the chance to take it in a special election, complicating Biden’s path to passing legislation.

But neither of those problems is a dealbreaker. Vice-presidential candidates don’t need to be electrifying campaigners for the ticket to win — just ask vice presidents Mike Pence and Al Gore. And Baldwin may be a sympathetic figure on a debate stage next to Pence, who is very conservative on LGBT issues. While Democrats should be concerned about losing Baldwin’s seat, if Biden believes that Baldwin is the best choice for vice president, he should pick her and sort out the down-ballot consequences later.

Biden has a huge responsibility in this election. If Trump wins a second term, Americans will understandably start to see him as the new normal. Attacks on the press, Twitter outbursts, constant lying, authoritarian saber-rattling, complete incompetence, disregard for expertise — all these features of Trumpism will be permanent parts of our politics. Biden has a chance to make Trump a historical aberration. If he’s serious about taking that chance, he’ll make smart moves such as picking Baldwin as his running mate.

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