Former President Trump and President Biden launched into a battle for Nikki Haley's supporters on Wednesday, as she suspended her challenge of Trump for the GOP presidential nomination.

Why it matters: One of the biggest questions in the race for the White House is how Haley voters — a potentially difference-making chunk of the GOP electorate with moderates reluctant to back Trump — will choose in November.

• Winning over this voting bloc, especially in suburban areas in battleground states, could be key to winning the general election.

Driving the news: Haley — who has called Trump unfit for office and questioned whether he'd follow the Constitution — didn't endorse her fellow Republican, and instead said he will have to earn her voters' support.

• Trump has some making up to do with Haley's backers. He repeatedly has called his former UN ambassador "Birdbrain," and in January warned that anyone contributing to Haley's campaign would be "permanently banned from the MAGA camp."
• On social media Wednesday, Trump made a caustic appeal to Haley supporters, writing: "Nikki Haley got TROUNCED last night" and belittling her wins in D.C. and Vermont — while in the same message inviting those supporters to "join the greatest movement in the history of our nation."

Biden — whose campaign has been using Haley attack lines against Trump for weeks — took a more inclusive tone.

• "Donald Trump made it clear he doesn't want Nikki Haley's supporters," Biden said in a statement.
• "I want to be clear: There is a place for them in my campaign."

Haley campaign spokesperson Olivia Perez-Cubas highlighted the differences between the Biden and Trump statements, posting on X: "A tale of two statements..."

Zoom in: Haley argued on the campaign trail that Trump cannot unite the GOP and win in November, pointing to polls that suggested she'd beat Biden.

• Trump dominated the early GOP contests and won 14 out of the 15 Super Tuesday states, but there were some warning signs for the former president in the key battleground of North Carolina.
• Exit polling in the state — which Biden narrowly lost to Trump in 2020 — indicated that 80% of Haley voters wouldn't necessarily vote for the GOP nominee in November, according to CNN exit polling.
• Two-thirds said they didn't believe Trump was physically or mentally fit to be president.

What to watch: "It is now up to Donald Trump to earn the votes of those in our party and beyond it who did not support him," Haley said Wednesday.

• "This is now his time for choosing."

Go deeper: Trump's demographic problem