Sen. Elizabeth Warren of Massachusetts became the first 2020 Democratic White House challenger to announce her “exploratory committee,” a legal device that allows candidates to receive donations and to hire staff in preparation for a full-fledged presidential candidacy. Make no mistake; presidential exploratory committees are always composed of unreconstructed optimists who invariably discover that millions of Americans the pollsters have somehow missed are openly yearning to support the candidate-in-waiting.

Sen. Warren more than meets a couple of tests every candidate faces. She has a compelling personal story. A native of Oklahoma, she grew up in humble circumstances. She was a young single mother of two who, with no family connections, went to law school and would become not just eventually a Harvard Law School professor but the champion of America’s struggling middle class and the scourge of Wall Street, as she successfully advocated for the creation of the Consumer Financial Protection Bureau. Maybe even more importantly, Warren knows more than most presidential candidates ever do just what she believes and why.

But she may have already made a fatal political mistake. Warren lived in, went to college and law school in and taught in Washington, D.C., Texas, New Jersey, Michigan and Pennsylvania before accepting an invitation to be a professor at Harvard Law School, which meant moving to Massachusetts. As a native of Massachusetts with an admitted excess of pride in the commonwealth’s political history and traditions, I am still forced to admit that over the past six decades, being from Massachusetts has been the kiss of death for national candidates.

Think about it. A single Massachusetts county, Norfolk, all by itself gave the nation four native sons who became president: John Adams, John Quincy Adams, John F. Kennedy and George H.W. Bush (who, of course, left the Bay State in his rearview mirror to run from Texas). President Calvin Coolidge had been a Massachusetts mayor and governor. Both John McCormack and Tip O’Neill, proud natives, were, in the past half-century, speakers of the House.

But something happened. Somehow and somewhere, Americans lost their confidence and appetite for national candidates from Massachusetts. Who was Richard Nixon’s running mate when he lost in 1960? Henry Cabot Lodge of Massachusetts, that’s who. What did 2012 Republican presidential nominee Mitt Romney, 2004 Democratic presidential nominee John Kerry, 1988 Democratic presidential nominee Michael Dukakis and defeated Democratic presidential candidates Paul Tsongas (in 1992) and Ted Kennedy (in 1980) all share? Each and every one of them ran — and lost — as a Massachusetts resident. Romney has now returned to national office as a U.S. senator from not Massachusetts, you may have noticed, but Utah.

Since John F. Kennedy’s 1960 election as the first Catholic president, Americans have elected chief executives from Texas (three), New York (two), Georgia, California, Arkansas and Illinois. Elizabeth Warren has many commendable qualities and a distinguished public record. But she may already be doomed for simply having one, admittedly unfair, disqualification: her Massachusetts home address.

— Mark Shields is a columnist with Creators Syndicate.