Rep. Steve King, R-Iowa
CNN  — 

The coronavirus pandemic halted much of the country’s voting in March, but primaries that were delayed will begin to make their return nearly three months later in eight states and the District of Columbia on Tuesday.

Mail-in voting will be far more prevalent, and expectations are that turnout will be down due to coronavirus fears, but the return of voting is the latest sign that the United States is reopening after months of stay-at-home orders and forced closings.

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Tuesday’s presidential primaries in DC, Indiana, Maryland, Montana, New Mexico, Pennsylvania, Rhode Island and South Dakota could see former Vice President Joe Biden, the presumptive Democratic nominee, officially lock up the number of delegates needed to win the nomination at the party’s convention later this year.

But the most closely watched races on Tuesday are down-ballot contests, especially in Iowa, where controversial GOP Rep. Steve King is facing a stout primary challenge and Democrats in the state will have to sort out their four-way Senate primary.

Here is what to watch for on Tuesday night:

Could this be the end for Steve King in Iowa? (Democrats also have a decision to make)

In the Republican primary for Iowa’s 4th Congressional District seat, state Sen. Randy Feenstra is the leading contender to oust incumbent King, whose long history of racist remarks might have finally put his grip on the seat in doubt.

King won a narrow victory over Democrat J.D. Scholten, who is running unopposed on Tuesday, in 2018.

But Feenstra’s well-funded bid could be hobbled by the large field. If none of the Republican candidates hits a 35% threshold, per state rules, the nomination will be decided at a district convention.

Feenstra’s campaign has zeroed in on King’s diminished standing on Capitol Hill, where he was stripped of his committee assignments last year after asking, in a New York Times interview, “how” terms like “white nationalist” and “white supremacist” became offensive.

King told the Sioux City Journal in May that House GOP leader Kevin McCarthy of California had agreed to push for him to be reassigned and have his seniority restored. But McCarthy publicly shot down the claim.

“Whatever you think of Steve King, it’s clear he’s no longer effective,” said Bob Vander Plaats, the influential evangelical leader, in a recent ad for Feenstra.

Democrats will also have a decision to make: A primary will decide who challenges incumbent GOP Sen. Joni Ernst in November.

Businesswoman Theresa Greenfield is the favorite, entering with the support of national groups; retired Navy Adm. Mike Franken was endorsed by The Des Moines Register; Eddie Mauro, a businessman, made an unsuccessful bid for the Democratic nomination in the state’s 3rd Congressional District in 2018; and Kimberly Graham, a lawyer, is the standard-bearer for the party’s progressive wing.

Will Biden officially clinch the nomination?

Eight weeks after the Democratic primary unofficially ended with Sen. Bernie Sanders’ exit from the race, Biden has not yet won the 1,991 delegates needed to officially clinch the party’s nomination.

Biden’s pledged-delegate count stands at 1,554, according to CNN’s delegate tracker. That leaves him 437 short of the threshold, with 479 available in Tuesday’s primaries.

That means Biden would officially lock up the Democratic nomination if – as the only active candidate remaining in the race – he amasses the overwhelming majority of support from the party’s primary voters.

It’s no sure thing: Sanders has said he will stay on the ballot and continue amassing delegates in a bid to influence the party’s platform. And if he hits 15% in some regions, it would limit Biden’s delegate haul.

And while neither Biden or Sanders has done any campaigning in the states, there are some heated down-ballot primary races featuring progressive officials and challengers, meaning the senator from Vermont could win some votes – and more delegates to the party’s convention.

Remember voting?

The coronavirus halted almost all of American life in March, and primary days were not spared.

It has been three months since voters in any significant number of states have cast ballots on the same day. While some voting has gone on during the pandemic – namely a chaotic primary in Wisconsin on April 7 – it has been on a markedly smaller scale than when well over a dozen states voted in early March. Even the primary contest has changed in that time: Biden vs. Sanders is no more, and the looming contest between Biden and President Donald Trump has taken a backseat to the virus and racial unrest across the country.

Four of the eight contests on Tuesday – Indiana, Maryland, Pennsylvania and Rhode Island – were rescheduled from earlier in the year due to coronavirus. And Montana has implemented a full vote-by-mail strategy.

The voting, especially on the presidential primary level, is significantly lower stakes, given Biden has all but locked up the nomination; some contests could feature lower turnout than if they had been held earlier this year.

Mail-in voting gets a test

Trump has spent months attacking mail-in voting, arguing without evidence that it leads to more fraud and suggesting that he will legally challenge any state that attempts to increase access ahead of November’s general election.

“People cheat. Mail ballots are a very dangerous thing for this country, because they’re cheaters,” Trump said in early April, citing no evidence. Mail ballot fraud is exceedingly rare in part because states have systems and processes in place to prevent forgery, theft and voter fraud.

On Tuesday, though, even Republican-controlled states will allow expanded access to mail-in voting as the pandemic continues to grip the country.

The best example of this is Montana, where Republican Secretary of State Corey Stapleton has not only encouraged people to vote absentee, but his office also has worked with each county to carry out an election entirely by mail. Gov. Steve Bullock, a Democrat, gave each county the option to conduct the election by mail, and each of the state’s 56 counties opted to do so.

Other states, like Maryland, Indiana and Pennsylvania, have increased the use of mail-in ballots to prevent many people from gathering in close quarters to vote on Tuesday.

While Republicans have argued that expanded mail-in voting in primaries is markedly different than during a general election, the success or failure of Tuesday’s contests will be used as a data point on whether to expand access in November. The stakes are particularly high in Pennsylvania, the most populous state voting on Tuesday and the only one that will be a key presidential battleground in November.

Celebrity status or local roots?

That’s the question at the heart of a hotly contested congressional primary between former CIA operative Valerie Plame and longtime New Mexico activist Teresa Leger Fernandez in Northern New Mexico.

Plame, who rose to national prominence when her identity was revealed during the George W. Bush administration in 2003, has looked to turn her well-known name into a campaign that both state and national Democrats could buy into. Her campaign was launched with a splashy video – titled “Undercover” – that called back to her CIA roots and featured the candidate driving an American sports car backward.

But the primary race in the Democratic district is crowded and Leger Fernandez, a longtime local political figure, has locked down more endorsements from newspapers, national organizations and national Democrats, including Sen. Elizabeth Warren of Massachusetts and Rep. Alexandria Ocasio-Cortez of New York.

The incumbent in New Mexico’s 3rd District, Rep. Ben Ray Lujan, is leaving his seat and running for the Senate from New Mexico.