I don't know whether Bernie Sanders should be president. But if the argument is about "electability," a case exists that Sanders is not merely electable, but may be the most electable Democrat running right now. Democrats who want to defeat Donald Trump in 2020 should not assume that Sanders is a politically risky choice — even though that is the conventional wisdom — and instead look dispassionately at the arguments for and against his supposed electability.

More than mere fairness is at stake here. Donald Trump, who represents a grave danger to the United States and the world. His initiatives on global warming and immigration, his economic and foreign policies and his personal corruption are all existential threats to the survival of the free world, as well as severe moral crises for our country. If he is to be defeated, the Democrats must look at whether each of the leading candidates — former Vice President Joe Biden, Sen. Elizabeth Warren, Mayor Pete Buttigieg and Sanders — has a realistic argument for how they could win.

That argument exists for Sanders. It's possible that, as Fox Business Network host Trish Regan told me in March, he's simply too far left. Many people make that same argument, from the axiomatic position that a leftist or socialist is inherently unelectable. Yet when I reached out to assorted political experts to get their thoughts on Sanders' electability, I found more complex responses.

Before contacting these people, I identified five hypothetical arguments suggesting that Sanders is the most electable candidate. He has rebounded a bit in the polls since recovering from his recent heart attack, and is currently at or near the top in both Iowa and New Hampshire. His supporters are enthusiastic and will vote for him no matter what, which could lead to higher turnout for him in both the primary and general elections. Voters may care less about ideology than character, which could give Sanders an edge if he is perceived as compassionate and sincere in contrast to the opportunistic and shallow Trump.

If Trump shifted the Overton Window (that is, the frame of what is considered acceptable in mainstream political debate) in 2016, it's entirely conceivable that Sanders could do it again. For that matter, Sanders' ideas aren't even that radical in the first place; they're basically an updated version of Franklin Roosevelt's New Deal, which got him elected four times.

Finally, and perhaps most importantly, Sanders has consistently led Trump in head-to-head polling in battleground states, and thus has a plausible Electoral College strategy. As a resident of one such state, Pennsylvania, I encounter this daily, at least on an anecdotal level.

"Conventional wisdom routinely fails to grasp the simmering anger that’s fueled by extreme income inequality," journalist Norman Solomon, co-founder and national coordinator of RootsAction.org and a Sanders delegate to the 2016 Democratic National Convention, told Salon by email. He was making what one could call the "populist wave" argument:

And when the electoral door is closed for progressive populism, the only other door open leads to right-wing demagoguery of the sort that Trump personifies. In the 2020 general election campaign, Democratic presidential nominee Bernie Sanders would fling a progressive populist door wide open.

After dismissing the "mass-media myth" that Democrats need to nominate a moderate like Joe Biden to win (and invoking the example of Hillary Clinton in 2016), Solomon argued that

yes, there are disaffected Republicans to be had, but not many — compared to the huge potential for increasing turnout among people of color, lower-income voters and young people. More than any other candidate, Sanders has enormous potential to inspire that kind of turnout.

In other words, Solomon posits that Sanders' democratic socialist ideology — the very thing that lead many to conclude he can't possible win — is in fact his greatest electoral strength.

By contrast, Kyle Kondik, managing editor of the nonpartisan political science site Sabato's Crystal Ball, offered the more traditional view that Sanders' ideology could just as easily be a liability as a strength.

"There is some evidence that voters punish more ideologically extreme candidates, and remember that for as extreme as Trump was and is on some issues and in his personal behavior, he also altered the GOP’s messaging on issues such as entitlements and free trade in ways that seemed to be electorally useful," Kondik told Salon by email. Sanders could also benefit because "he tends to emphasize economic and class issues over cultural and social ones," Kondick continued, which may be "a better approach for Democrats in a general election setting, because a number of the most important swing voters are probably less economically conservative than they are culturally conservative."

At the same time, Kondik suggested that Sanders' policies could be perceived as overly ambitious "in a time of relative peace and prosperity, where such far-reaching proposals may be out of step with the electorate — particularly affluent, highly-educated professionals who are new to the Democratic Party and who dislike Trump but may be leery of Sanders’ program."

Kondik was also cautious about predicting that Sanders would inspire higher turnout, arguing that it was an "open question" whether he could do so among "non-white voters, particularly African Americans" and the "small but crucial number of 2016 Trump and/or third party voters."

Finally we come to Allan Lichtman, an American political scientist at American University whose book "The Keys to the White House" defines a formula that has accurately predicted every presidential election since 1984. Unlike Solomon, Lichtman doesn't think Sanders' ideology will help, and unlike Kondik, he doesn't think it is likely to hurt. Instead, he believes ideology is ultimately irrelevant.

"I have said many times that 'electability' is a word that should be abolished from the political lexicon," Lichtman explained by email. "According to my 13 keys to the White House, presidential elections are primarily votes up or down on the strength and performance of the party holding the White House. Only one key pertains to the challenging candidate and it turns against the incumbent party only in the very rare case where the challenger is truly charismatic and inspirational. Otherwise traditional calculations of electability are meaningless." He cited the examples of supposedly electable Democrats like Michael Dukakis in 1988, Al Gore in 2000, John Kerry in 2004 and Hillary Clinton in 2016, all of whom lost.

"My advice to voters is vote for who you believe in and stop trying to decipher 'electability,'" Lichtman advised.

In the Solomon, Kondik and Lichtman schools of thought, we can see a full spectrum of possibilities. Only Kondik holds that Sanders' ideology could hurt him — largely based on consistent poll results showing that Biden runs strongest against Trump both in the total popular vote and in the Electoral College.

"Bernie Sanders has an impressively solid base of committed supporters, but there's scant evidence that a majority of Americans are ready to embrace his European-style democratic socialism," Will Marshall, founder of the Progressive Policy Institute, told Salon by email. "I think there are lots of suburbanites across the Midwest who have growing doubts about Trump, but might see him as the lesser evil if Democrats nominate someone they view as hostile to the free enterprise system."

Marshall later added, "Mayor Pete [Buttigieg] is rising in part because Democratic primary voters view him as less doctrinaire than Elizabeth Warren, who is being dragged down by her support for Medicare for All. And if she's too far out of the left limb, Bernie's even farther."

Norman Solomon's school of thought — that a candidate who inspires voters can win by tapping into deep political angers — has played out successfully in recent history. Before 2016, Americans had never elected a president who lacked any political or military experience, let alone someone who had been divorced twice and was primarily known to the public as a reality TV star. Yet Donald Trump is now president because he defied conventional wisdom at every stage.

In the Solomon, Kondik and Lichtman schools of thought, we can see a full spectrum of possibilities. Only Kondik holds that Sanders' ideology could hurt him — largely based on consistent poll results showing that Biden runs strongest against Trump both in the total popular vote and in the Electoral College.

"Bernie Sanders has an impressively solid base of committed supporters, but there's scant evidence that a majority of Americans are ready to embrace his European-style democratic socialism," Will Marshall, founder of the Progressive Policy Institute, told Salon by email. "I think there are lots of suburbanites across the Midwest who have growing doubts about Trump, but might see him as the lesser evil if Democrats nominate someone they view as hostile to the free enterprise system."

Marshall later added, "Mayor Pete [Buttigieg] is rising in part because Democratic primary voters view him as less doctrinaire than Elizabeth Warren, who is being dragged down by her support for Medicare for All. And if she's too far out of the left limb, Bernie's even farther."

Norman Solomon's school of thought — that a candidate who inspires voters can win by tapping into deep political angers — has played out successfully in recent history. Before 2016, Americans had never elected a president who lacked any political or military experience, let alone someone who had been divorced twice and was primarily known to the public as a reality TV star. Yet Donald Trump is now president because he defied conventional wisdom at every stage.