Donald Trump won the Republican presidential nominating contests in Virginia and North Carolina on Tuesday, Edison Research projected, as he sought to force rival Nikki Haley from the race on the biggest voting day of the primary calendar and set up a rematch with Democratic President Joe Biden.
Voters in 15 states and one US territory were casting ballots for president on Super Tuesday, with polls scheduled to close throughout the evening until Alaska wraps up the day at midnight EST (0500 on Wednesday GMT).
Immigration and the economy are leading concerns for voters in both parties, Edison exit polls in California, North Carolina and Virginia showed. A majority of Republican voters in those states said they backed deporting illegal immigrants; Trump, who frequently denigrates migrants, has promised to mount the largest deportation effort in US history if elected.
Katherine Meredith, a 65-year-old homemaker, voted for Trump in California's Huntington Beach, which includes a significant Trump base despite California's strong Democratic leanings.
"The border is a complete catastrophe," Meredith said.
Biden was expected to sail through the Democratic contests, though activists opposed to his strong support of Israel called on Muslim Americans and progressives to cast "uncommitted" protest votes in Minnesota as they did before in Michigan.
The president easily won in Iowa, North Carolina and Virginia, Edison projected.
Trump, who has dominated the Republican campaign from the start despite a litany of criminal charges, has swept all but one of the contests so far, winnowing a sprawling Republican field of candidates down to two.
While Trump cannot win enough delegates to formally clinch the nomination on Tuesday, another commanding performance would further pressure Haley, a former U.N. ambassador under Trump and a former South Carolina governor, to drop her long-shot bid.
The day's contests will award more than one-third of Republican delegates - and more than 70% of the number needed to secure the nomination.
'We're going to win every state tonight'
Trump told Fox that his focus was on Biden, adding: "We're going to win every state tonight."
His advisers have said they expect him to eliminate Haley mathematically no later than March 19, when two-thirds of the states will have voted. Trump is scheduled to begin his first criminal trial six days later in New York, where he is charged with falsifying business records to conceal hush money payments to a porn star during his 2016 presidential run.
Biden said in an interview on Power 98 FM, a hip-hop and R&B radio station that serves Charlotte, North Carolina, that the elections were a chance to take on "the extreme division and violence the MAGA Republicans are pushing," using the acronym for Trump's Make America Great Again campaign slogan.
Voters were also casting ballots in down-ticket races, including two contests in California to identify potential successors to the late Democratic US Senator Dianne Feinstein and the recently deposed Republican House Speaker Kevin McCarthy.
In Arizona, independent US Senator Kyrsten Sinema, a former Democrat, said she would not run for reelection, setting up a battle for her seat that could determine control of the closely divided Senate next year.
Pop megastar Taylor Swift encouraged her fans to vote in a post on Instagram, though she did not endorse specific candidates. Biden's campaign is hopeful Swift will eventually back his candidacy, as she did in 2020.
Haley's challenge has highlighted some of Trump's potential general election vulnerabilities. She has reached 40% in some state contests and argues that shows independents and moderate Republicans harbor unease about a second Trump term.
About one-third of North Carolina voters said Trump would not be fit to serve as president if he was convicted of a crime, while in Virginia, 53% said he would be fit for the office if convicted.
In addition to the New York case, Trump faces separate federal and Georgia state charges for election interference, though it is unclear whether either case will reach trial before November's election. He also faces federal charges for retaining classified documents after leaving office.
Trump has pleaded not guilty in all four criminal cases.