While some people believe the DNC secretly picks the 2020 nominee, the reality is YOU get to decide who runs against Trump.
Right now, there’s a lot of attention on Iowa and New Hampshire, but that’s because they get to weigh in first. The Iowa caucus is on February 3 and the New Hampshire primary is about a week later, on February 11. Everybody’s vote is worth the same, so in theory, it shouldn’t matter who goes first. But the fact is if you do well in Iowa and New Hampshire, it’s easier to raise money, it’s easier to get press, and build excitement so you get a snowball effect that makes it much more likely to win the other contests.
One thing that’s not great about Iowa and New Hampshire having so much influence is they’re not the most diverse states. Iowa has a 90% white population, whereas New Hampshire has as 93% white one. The DNC realized this was a problem, and in 2008, they moved up the dates for South Carolina, whose population is comprised of 31% people of color and Nevada which has about 26%.
The candidates that survive that round of voting make it to Super Tuesday on March 3, when 15 states and American Samoa have their primaries. The remaining states will have their primaries between then and June. Then it is a matter of winning delegates and super delegates.
However, as of 2020, super delegates are not even part of the first round of voting at the convention. So the power is in the voters hands.