They called him the "boy orator," and he never stopped talking. William Jennings Bryan from the mid-western farm state of Nebraska spoke to the passions of his time, especially the free coinage of silver to supplement gold as the national currency. This was intended to put more money into the pockets of Americans during an economic depression.

That issue and his prodigious voice carried Bryan to the 1896 Democratic convention, where he was not considered a front-runner for the Presidential nomination. He was only 36 and had lost a U.S. Senate election two years before. But then came the speech of his lifetime in support of free silver:

"We will answer their demand for a gold standard by saying to them: 'You shall not press down upon the brow of labor this crown of thorns. You shall not crucify mankind upon a cross of gold.'"

The convention went wild and Bryan could barely escape the clutches of his admirers. Off he went to make still more speeches, 27 on the day before the election. Yet he lost to Republican William McKinley, who was solid on the gold standard if not quite so exciting to voters.

Move ahead to 1940 with America facing the Second World War. Republicans were split between so-called isolationists who wanted at all costs to avoid war and internationalists who urged preparedness.

Wendell Willkie, a candidate from the internationalist wing, was a former Democrat who had never held public office. Though he had been a large utility company executive, he was friendly, folksy in rumpled suits. "The barefoot boy from Wall Street," scoffed a Democrat. He did not seem to have much of a chance until the isolationists split their vote, and a well rehearsed cry went up for Willkie, according to a radio announcer:

As chairman Joe Martin put it, 'Out of the hearts of patriotic Americans came the chant: We want Willkie!'

But he faced an opponent of still greater popularity, two-term President Franklin Roosevelt. No American President had ever served more than two four-year terms, a tradition begun by the first chief executive, George Washington. But Roosevelt, or FDR as he was called, thought he should remain in office as war approached.

He had eager successors within the Democratic Party, and many Democrats opposed a third term. The President seemed undecided. He did not even attend the convention much to his delegates' dismay. Then as his candidacy seemed in doubt, party loyalists stormed the aisles chanting: "We want Roosevelt," and a sepulchral voice bellowed from below the hall: "Chicago wants Roosevelt! Illinois wants Roosevelt! New York wants Roosevelt! America wants Roosevelt!"

That did it. Chicago's strategically placed superintendent of sewers climaxed the proceedings, and FDR was nominated for a third term. In his acceptance speech, he explained his decision:

"When the conflict first broke out last September, it was still my intention to announce clearly and simply, at an early date, that under no conditions would I accept reelection. It soon became evident, however, that such a public statement on my part would be unwise from the point of view of sheer public duty." FDR defeated Republican Willkie to win a third term and then went on to win a fourth, dying in office shortly after.

Those were the days, says Alan Brinkley, professor of history at Columbia University. He writes in the New York Times that today's conventions are "carefully packaged infomercials in which delegates serve as well-behaved studio audiences, dutifully watching the proceedings on giant video screens. Everyone involved, candidates, parties, delegates, news media, has collaborated in this march toward banality and iron-fisted control."

But then in time of war and crisis, says Professor Brinkley, it is possible for the script to go awry and genuine passion and protest emerge. In that case, a convention just might recover some of the zest of yesteryear.