Tuesday, Aug. 20 isn’t the big day. But it is a big day.

Voters all over Florida will head to the polls to cast a ballot in the primary, setting the field for the Nov. 5 general election. Incumbent Republicans like U.S. Sen. Rick Scott will have to fend off opponents from their own party before moving on to November. Others, like U.S. Rep. Anna Paulina Luna, who didn’t draw primary challengers will soon know their general election opponents.

Some races down the ballot will be decided Tuesday. For example, in the Hillsborough County District 3 school board race, voters will decide between Myosha Powell, who was endorsed by Gov. Ron DeSantis, and Jessica Vaughn, who’s been backed by the Florida Democratic Party.

A winner could be chosen in school board races with more than two candidates if a candidate wins more than 50% of the vote. If not, the top two finishers advance to the general election.

With so many results set to pour in, here are the major storylines to focus on.

1. Which Democrat will challenge Rick Scott?

In the Democratic U.S. Senate primary, Debbie Mucarsel-Powell has benefited from support from her national party. When President Joe Biden came to Tampa to campaign, Mucarsel-Powell was the only Democrat in her race who spoke at the rally. Others were not offered time.

Scott has largely ignored the Democrats other than Mucarsel-Powell, training much of his fire on the former U.S. representative from South Florida. In multiple cities, Scott has paid for mobile billboards calling Mucarsel-Powell a “socialist” — a label the Democrat vehemently denies.

Mucarsel-Powell is running against former attorney Brian Rush, Navy veteran and technology executive Stanley Campbell and Army veteran Rod Joseph.

Scott faces two primary challengers, Keith Gross and John Columbus. Both Mucarsel-Powell and Scott are expected to cruise to victory.

Mucarsel-Powell’s campaign committee has reported about $14.4 million in fundraising, according to the Federal Election Commission. That’s more than 10 times what her three opponents’ committees have raised combined. Scott, one of the richest members of the U.S. Senate, has loaned his campaign more money than his opponents have raised put together.

“I know that I can defeat Rick Scott, and that’s what I’ve been focusing on, but we need to get through the primary first,” Mucarsel-Powell said in an interview this month. “I’m not taking anything for granted.”

Campbell appears to be Mucarsel-Powell’s closest competitor. In June, the labor group Florida AFL-CIO endorsed him, and he’s loaned his campaign $1 million.

In an interview, Campbell said it was clear the Democratic Party had picked Mucarsel-Powell as its preferred candidate early on.

“It’s hard enough fighting the battles of an election, but it’s much more difficult when you have to go against (Senate Democratic Leader) Chuck Schumer in your race.”

Scott’s team, meanwhile, is projecting confidence. They claim that few voters know who Mucarsel-Powell is and that she could be in for an embarrassing showing.

“The fact that Stanley Campbell’s name comes first on the ballot is a real fear for her,” said Scott political adviser Chris Hartline.

2. How will DeSantis’ school board candidates do?

For years, Florida’s Republican governor has made partisan control of local education policy one of his top priorities. In 2022, DeSantis endorsed 30 candidates, and 80% of his picks won.

This year, DeSantis is following that effort with a slate of 23 endorsements. In a July post to X, DeSantis wrote that his preferred candidates “have pledged to serve with a focus on student success, parental rights, and curriculum transparency.”

Five of his picks this cycle come in Pinellas and Hillsborough counties. In Hillsborough, the board is mostly composed of registered Democrats; DeSantis is hoping to change that.

Three of DeSantis’ candidates have just one opponent, meaning their races will be decided Tuesday. There’s Hillsborough’s District 3 race between Powell and Vaughn. Incumbent Laura Hine will have to fend off a challenge from the DeSantis-backed Danielle Marolf in Pinellas’ District 1. And DeSantis’ pick Erika Picard is hoping to unseat Eileen Long in Pinellas’ District 4.

Edwin Benton, a professor of political science and public administration at USF, said Tuesday gives Democrats an opportunity to showcase how serious they are about contesting races up and down the ballot.

“It’s very important for the Democrats to show up, because in past elections, they have been unenthusiastic,” Benton said.

3. What the primary means for November

Every major election cycle, prognosticators, journalists and voters spend months poring over polling data hoping to glean insights into American politics. Who will win the presidency? How will voters decide on major consequential constitutional amendments about abortion and legal marijuana?

In theory, Florida’s primaries, held a dozen weeks before Election Day, offer a real-world look at how motivated people are to get to the polls. Surely an August election offers insight into how people will vote, right?

Not exactly, political experts say.

“I wouldn’t really look too closely at turnout numbers for August and draw any conclusions about what it might mean for November,” said Michael Binder, a professor at the University of North Florida who runs that institution’s public opinion research lab.

First, there’s the issue of no-party-affiliated voters. Although dedicated citizens who don’t belong to a party will vote in Tuesday’s primary, they won’t be able to choose Democratic or Republican candidates in high-profile races for Congress. Instead, they’ll be left to pick local school board members, judges and other municipal officials.

That means we will learn almost nothing about the millions of no-party-affiliated Florida voters who don’t show up Tuesday.

Many who are affiliated with a party will also skip Tuesday’s primary. Those who vote in primaries are typically the most dedicated political observers in the state, Binder said.

General elections in November are decided by everyone else.

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