3 things to watch for in Tuesday's primaries

CHICAGO -- The presidential nominations are locked up -- but the primaries remain, along with any tea leaves they may provide.

Ohio's GOP Senate primary was the headliner Tuesday, with car salesman Bernie Moreno considered by several strategists to be the slight favorite, running with former President Donald Trump's endorsement against state Sen. Matt Dolan and Secretary of State Frank LaRose. All are running as staunch conservatives, though some dividing lines have emerged on policy and their approach to Trump himself.

The Associated Press projected Moreno won the Republican nomination.

He will get the chance to run against Democratic Sen. Sherrod Brown, in one of the most competitive Senate races of the year.

And while Trump and President Joe Biden have locked up the delegates needed to win their respective parties' nominations, primaries in Arizona, Florida, Illinois, Kansas and Ohio could reveal any lingering grumbling in either party base over their presumptive nominees.

The Associated Press and ABC News projected Biden and Trump secured their parties nominations in Ohio, Illinois, Kansas and Florida.

Trump and Biden are also expected to easily win primaries Tuesday in Arizona, banking more support after becoming their parties' presumptive nominees last week.

All the while, the battle for the House will continue to get fleshed out Tuesday night.

Here are three things to watch for in Tuesday's primaries.

Ohio primary a political knife fight

Ohio's GOP Senate primary headed toward a ferocious finish after Moreno, Dolan and LaRose have savaged each other for months.

National Republicans have helped clear several Senate primary fields in favor of a favored candidate, but with no clear preference in Ohio, the race has remained crowded and contentious.

Moreno has given Trump a political bear hug, earning his endorsement and rallying with him and other allies in Dayton on Saturday. Dolan has run as a more traditional conservative, earning the support of Gov. Mike DeWine, R-Ohio, and former Sen. Rob Portman, R-Ohio, while saying he supports Trump's policies without as much personal fealty. And LaRose has also run in the Trump lane, though he has been able to keep up with the high spending levels from Moreno and Dolan and suffered setbacks by not gaining Trump's endorsement.

Keeping up with recent races in Ohio, the primary has resembled a political knife fight, with candidates accusing each other of phoniness in their ideology and deep character flaws.

The primary was capped off by a story last week from the Associated Press saying that an email address associated with Moreno's company was used to set up an online profile seeking "Men for 1-on-1 sex." Moreno's campaign has denied that he had access to the email used for the account, and a past intern has said he set it up as a prank.

Democrats have also spent millions of dollars in 11th hour ads intended to meddle in the race and elevate Moreno in the eyes of the conservative primary electorate by highlighting his ties to Trump.

The victor will emerge bloodied -- though, strategists said, with enough time to recover by the time he faces off in November against Brown, who is running against his state's partisan lean but brings a beefy resume and populist bona fides, making Ohio's Senate race one of the most competitive this year.

Lingering protest votes against Trump or Biden?

While Trump and Biden have handily won every primary state so far. But they also have faced different forms of protest votes.

Before former South Carolina Gov. Nikki Haley suspended her GOP presidential campaign, she routinely at least a quarter of the vote in primary states. And Biden has faced waves of criticism over his handling of the war in Gaza, with over 100,000 people backing "uncommitted" in the Michigan Democratic primary as a protest vote.

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Now, the protest votes in both parties are expected to diminish.

Haley dropped out of the race earlier this month, and few if any states have as favorable a Democratic electorate for a protest vote as do Michigan or other states like Minnesota or Washington.

However, the chances of a protest vote remain.

Haley, who dropped out after Georgia's early voting had already started but after Election Day there, still got over 13% of the vote on March 12. And Democratic voters could still sit out of the race, producing low turnout, or vote for more minor candidates like author Marianne Williamson.

As both candidates try to consolidate support among their party bases, operatives and observers alike are eyeing any signs of division heading into November.

Battle for House continues to take shape

While the presidential and Senate races will take center stage, the battle for the narrowly divided House of Representatives will continue to take shape Tuesday.

Ohio's 6th Congressional District is hosting a special election to complete the term of former GOP Rep. Bill Johnson, who retired to become a college president, and a primary to be the Republican nominee in the race for a full term starting in January.

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The seat is deep red and features state Rep. Reggie Stoltzfus, state Sen. Michael Rulli and Rick Tsai, a chiropractor. Stoltzfus and Rulli are running as more staunch conservatives, though Rulli is also getting support from Defending Main Street, the super PAC arm of the more middle-ground Republican Main Street Partnership.

Ohio's 9th Congressional District, which is represented by Democrat Marcy Kaptur but also voted for Trump in 2020, is a top GOP target. Republicans caught a break when scandal plagued candidate J.R Majewski, who lost to Kaptur in 2022, dropped out of the race.

The two candidates left there are state Rep. Derek Merrin, who has drawn support from national Republicans, and former state Rep. Craig Riedel, who has been attacked over a resurfaced video of him criticizing Trump.

Illinois' 7th Congressional District is featuring a generational battle, with 82-year-old Rep. Danny Davis running for reelection against Chicago Treasurer Melissa Conyears-Ervin and activist Kina Collins, with the ultimate nominee all but guaranteed a win in November in the deep-blue seat.

Davis has several well-connected backers, including Gov. JB Pritzker, while Conyears-Ervin was endorsed by the Chicago Teachers Union and Collins has several allies in the activist community.

The Associated Press projected that Davis won the nomination.

If the 7th Congressional District features internal Democratic fissures, Illinois' 12th Congressional District features Republican divides.

Rep. Mike Bost, who is running for reelection with Trump's endorsement, is facing off against Darren Bailey, a former state lawmaker and failed 2022 gubernatorial nominee who has found room to the right of the deeply conservative incumbent and touted policies like trying to remove Chicago from Illinois.

The Associated Press contributed to this report.