It's election day in the US.

Polls have opened in New York, Virginia and New Jersey, while California polling centres will open later.

This so-called "off year" election doesn't feature presidential or congressional races, but there are still several critical votes to watch tonight.

New York City will choose its next mayor, in a battle that has pitted a younger, progressive Democrat against a member of the party's old guard.

The states of Virginia and New Jersey will elect new governors, and the outcome of these contests could be bellwethers for next year's congressional midterm elections.

Californians also will decide whether to redraw their US House district maps in a rare mid-decade redistricting, as Democrats try to counter Republicans' efforts to give their party an advantage in next year's midterm elections.

New York City mayoral race

All eyes will be on the Big Apple as Zohran Mamdani, a 34-year-old state assemblyman, attempts a political upset in his bid to become New York City's youngest mayor in over a century.

Mamdani, a democratic socialist, shocked the political establishment when he bested former governor Andrew Cuomo in the Democratic primary this summer. Cuomo, undeterred, has continued to campaign as an independent. Meanwhile, Republican Curtis Sliwa has resisted pressure to drop out of the race to clear a path for Cuomo.

If Mamdani wins, he will become the city's first Muslim mayor. Democrats around the country will be watching to see if his laser-focus on cost-of-living issues like rent, groceries and wages could serve as effective messaging in future races.

Though Mamdani heads into election night with a suggested polling lead, the gap between him and Cuomo has narrowed. In the final stretch of the campaign, Cuomo has hammered Mamdani on crime and public safety, and said the young politician lacks the experience to lead America's biggest city.

California redistricting

California's Democratic leadership is asking voters for permission to redraw the state's congressional districts in the middle of the decade. That's unusual in California, which by law relies on a nonpartisan committee to draw its congressional maps once every decade, based on census data.

However, as Republican-led states like Texas and Missouri seek to hastily redraw their congressional maps to give their party an advantage in the 2026 midterm elections, California Governor Gavin Newsom wants to counter the losses with redistricting in his own state.

California's Proposition 50 would allow the temporary use of new congressional district maps through 2030. The campaign has drawn $158 million in donations, according to the Los Angeles Times, with Democratic proponents vastly outraising the Republican opposition effort.

Republicans in California, who hold only nine of the state's 52 US House seats, staunchly oppose the plan.

A University of California Berkeley/IGS poll suggests 60% of likely California voters support Proposition 50, while 38% oppose it. The breakdown was highly partisan, with 93% of Democrats saying they would choose "yes" and 91% of Republicans choosing "no".

New Jersey governor's race

New Jersey is considered a Democratic state, but polls indicate a close race between Democrat Mikie Sherrill and Republican Jack Ciattarelli. It's one of the two governor's races this year that could indicate how Americans feel about the current political climate.

Sherrill currently represents New Jersey's 11th District in Congress, and Ciattarelli is a former state assemblyman.

Despite leaning blue, the state has had Republican governors in the past. The last one, Chris Christie, served two terms between 2010 and 2018.

Rhetoric in the race has been heated. Ciattarelli and his supporters have run political advertisements featuring clips of Sherrill giving halting answers in interviews about her policies.

It also has drawn the attention of nationally known names from both parties. Democratic stars like former president Barack Obama and former transportation secretary Pete Buttigieg have campaigned with Sherrill. President Donald Trump attended a virtual rally for Ciattarelli, and conservative activist Jack Posobiec has backed him.

Virginia governor's race

Virginia's leadership usually swings between Democrats and Republicans, meaning the outcome of this year's gubernatorial election might serve as a bellwether for the electorate's mood.

No matter which candidate succeeds, the state will elect its first female governor this year. Voters will choose between Democrat Abigail Spanberger, a US congresswoman, and Republican Winsome Earle-Sears, the state's current lieutenant governor.

If Earle-Sears wins, she will become the first black woman elected to lead a US state in the nation's history.

Virginia is bordered by the liberal-leaning Washington DC to the north, where many residents work in the nation's capitol or for the federal government. But the state also has deep pockets of conservative voters throughout its rural districts, and swing voters.

Spanberger has highlighted the economic impact of Trump's cuts to the federal government, which have impacted Virginia's employment. Earle-Sears has touted Virginia's economy under Republican leadership. But she also has leaned into cultural topics like transgender issues, which Republicans used successfully as a wedge issue in last year's presidential election.

The Trump factor

Though he's not on the ballot, Trump's name looms over this election.

The New York City mayor's race is how the next leader of the city will deal with the Trump administration, which has meddled in the city's politics. Cuomo is pitching his experience as governor dealing with the first administration as a reason for voters to choose him.

The president has implied that he will penalize the city if voters choose Mamdani.

"It's gonna be hard for me as the president to give a lot of money to New York, because if you have a communist running New York, all you're doing is wasting the money you're sending there," Trump said in an interview with CBS programme 60 Minutes that aired Sunday. Mamdani rejects the communist label.

Trump kicked off the redistricting battle that led California to put Proposition 50 on the ballot, and has endorsed Ciattarelli in the New Jersey governor's race. (BBC)

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