Senate Democrats have a tough map in 2024, but some of the most interesting races are at the primary level.

The big picture: The most competitive matchups can be found in primaries in New Jersey and Utah, and general elections in Arizona, Montana, Ohio and Pennsylvania.

• Republicans have focused hard on recruiting solid, big-name candidates to avoid repeating mistakes from 2022.
• Democrats are counting on popular incumbents, messy GOP primaries and voters supporting abortion rights to give themselves an edge.

Arizona

Arizona has trended purple in recent elections.

• The contest is listed as a "toss up" in November, according to the Cook Political Report.

Sen. Kyrsten Sinema (I-Ariz.) has not announced a re-election bid but has until April 1 to decide.

• The single-term senator switched her party in 2022 but still caucuses with Democrats.

Rep. Ruben Gallego (D-Ariz.) is the likely Democratic nominee.

• Gallego is a former Marine who served in Arizona's House prior to joining Congress.

Kari Lake, the presumptive GOP nominee, has received an endorsement from National Republican Senatorial Committee Chair Steve Daines.

• Lake — an election denier — ran an unsuccessful gubernatorial campaign in 2022 against Democratic Gov. Katie Hobbs, who was secretary of state at the time.

Arizona's primary is scheduled for July 30.

Montana

Sen. Jon Tester (D-Mont.) is in his third term and is running for re-election in what the Cook Political Report says is a "toss-up" race.

• Among elected Montana officials, Tester has stood as a lone Democrat in a heavily GOP state.

Republican Tim Sheehy launched his Senate bid in June 2023.

• Former President Trump endorsed Sheehy, calling the former Navy SEAL officer "an American Hero and highly successful Businessman from the Great State of Montana," per a Truth Social post.

Montana's primary is slated for June 4.

New Jersey Democratic primary

Sen. Bob Menendez (D-N.J.) has not officially declared re-election in the state whose contest is listed by Cook Political Report as "likely Democrat."

• Menendez has faced calls to resign after being indicted on bribery charges regarding Egypt and more recent allegations in regard to Qatar.

Rep. Andy Kim (D-N.J.) announced his plans to challenge Menendez this past September.

• Kim said in a post on X that it was "not something I expected to do, but NJ deserves better."

Tammy Murphy, New Jersey's first lady, also jumped into the Democratic race in November.

• If elected, Murphy would be the first woman to represent the state in the Senate.

New Jersey's primary is set for June 4.

Ohio

Sen. Sherrod Brown (D-Ohio) is in his third term, with the race marked as a "toss up," per the Cook Political Report.

Three GOP hopefuls are aiming to beat Brown in a state where Trump dominated in 2016 and 2020.

• Ohio Secretary of State Frank LaRose hopped into the crowded race last July on the Republican ticket.
• Ohio state Sen. Matt Dolan joined the GOP race in January 2023. Dolan's family owns the Cleveland Guardians baseball team.
• Bernie Moreno, a Cleveland businessman, has received Trump's coveted endorsement.

Ohio's primary is set for March 19.

Utah Republican primary

The Republican-heavy state has a crowded list of GOP hopefuls looking to replace Sen. Mitt Romney (R-Utah), who is retiring. The Cook Political Report lists the contest as "solid Republican."

• Rep. John Curtis (R-Utah) announced his bid in January. Prior to serving in Congress, Curtis was the mayor of Provo, Utah.
• Trent Staggs announced his bid last May. He's the mayor of Riverton, Utah.
• Brad Wilson declared his candidacy in September 2023. Wilson is a former Utah House Speaker and a real estate developer.
• Brent Orrin Hatch is also on the Republican ticket. He's the son of the late Utah Sen. Orrin Hatch, who held the seat before Romney.

Utah's primary is slated for June 25.

Pennsylvania

The Keystone State could decide control of both the Senate and the presidency. Pennsylvania voted for Trump in 2016 then Biden in 2020.

• The Senate race is listed as leaning Democratic, per the Cook Political Report.

Sen. Bob Casey (D-Pa.) is looking to keep his post for a fourth term. Early polls have consistently shown Casey with a lead.

David McCormick, a former hedge fund CEO, is avoiding a potentially nasty primary — with no serious challengers listed on the state's candidate website.

• McCormick lost in the 2022 primary to Trump-backed candidate Mehmet Oz, who was ultimately defeated by Sen. John Fetterman (D-Pa.).

Pennsylvania's primary is set for April 23.

Other primaries on our radar

Other Democrat-heavy states are gearing up for their quickly-approaching primaries.

• Super Tuesday will feature California Democratic Reps. Katie Porter and Adam Schiff both hoping to make the November ballot as they try to outlast Steve Garvey, a Republican and former Dodgers MVP.

In Maryland, Rep. David Trone (D-Md.) is up against Prince George's County Executive Angela Alsobrooks as they seek to replace retiring Sen. Ben Cardin (D-Md.), with the primary slated for May 14.

• Whoever clinches the Democratic nomination will likely compete against former Maryland Gov. Larry Hogan (R), who announced his Senate bid on the Republican ticket earlier this month.

Go deeper: Who isn't running for re-election in the House and Senate in 2024