In 1844 the Democratic convention deadlocked when a former president, Martin Van Buren, couldn't outlast a political heavyweight from Michigan, Lewis Cass. After a series of inconclusive ballots, the convention unveiled a new political phenomenon, the dark horse candidate.
The nominee turned out to be James K. Polk, who was not even attending the convention in Baltimore. Back home in Tennessee, Polk learned days later he was running for president.
Eight years later, in 1852, the Democrats, after 49 ballots, nominated another dark horse, Franklin Pierce. And all that prodigious balloting was actually surpassed by that year's Whig convention, which nominated Winfield Scott on the 53rd ballot.
Brokered conventions persisted well into the 20th century, but we may never see anything like them again. Which might be just as well in today's world, as instead of enduring a staged convention on TV we might get roped into watching a reality series.
Illustration: James K. Polk, who was shocked to learn he'd been nominated at a brokered convention/Library of Congress
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