Any close race or race with many candidates is likely to have multiple ballots.
Read to the end of this article and also take note of the brewing controversy.
It is notable that while the MSM polls have Biden out front by a wide margin, it is Bernie (like Trump) who draws the enthusiastic, large crowds while Biden can’t fill a high school gym.
Also, they are hiding Biden just like they did HRC (because he hurts himself with public appearances) which is going to exacerbate the perception of a fixed primary to Bernie supporters who see their guy everywhere drawing big crowds while Biden does nothing.
Link: https://m.washingtontimes.com/news/2019/may/29/bernie-sanders-supporters-distrust-joe-biden-poll-/
The DNC rule change is already pretty radical considering how D primary works. (They don't have winner--take all in primary). I think low poll # of Sanders is due to Trump's economy. Keep it in mind, rise and fall of Sanders completely depends on economy. Before 2008 who gave Sanders a damn? If there is a recession coming, look at poll of Sanders, it will rise.
Carter? It doesn't happen that much any more. And it looks unlikely this time, too, unless something shifts.
For president, 1952. Adlai Stevenson was nominated on the third ballot at the Democratic Convention.
For vice president, 1956. Estes Kefauver was nominated on the second ballot at the Democratic Convention. He defeated JFK, who was ahead in the roll call. However, Sam Rayburn, who chaired the convention, kept the balloting open, allowing delegations to switch their vote to Kefauver. (There's actually YouTube video of the roll call.)
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Link: https://saraacarter.com/is-msm-and-dnc-colluding-against-bernie-sanders/
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