'Warning signs flashing': Biden, Trump struggle to lock up base voters ahead of first debate

As they prepare for their face-off on the debate stage next month, warning signals are flashing for President Biden and former President Donald Trump in their 2024 election rematch - as they both appear to struggle to lock up their base voters.

More than two months after she dropped out of the Republican presidential nomination race, zombie candidate Nikki Haley is still grabbing sizable support in the GOP primaries at the expense of Trump.

And Biden is continuing to deal with a persistent "uncommitted" vote protesting the president's support for Israel in its war with Hamas in Gaza.

"You going to see most Democrats and most Republicans come home. But there are so many warning signs flashing in these primaries," David Kochel, a longtime Republican consultant and veteran of numerous GOP presidential campaigns, told Fox News Digital.

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One week after Haley won 22% of the vote in Indiana's GOP presidential primary, where independents and Democrats could vote, it was supposed to be a different story on Tuesday as Maryland, Nebraska, and West Virginia held mostly closed Republican contests.

But according to unofficial results, Haley grabbed 21% support in Maryland and 18% in Nebraska.

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And Haley performed strongest in suburban areas in both states, as she also did in earlier primaries held after she suspended her presidential bid. It's another potential general election problem for Trump, who is currently making history as the first former or current president to stand trial in a criminal case.

"It might just be that Republicans want one last chance to express their dissatisfaction with the nominee and they’ll come home," Kochel, who remained neutral in the 2024 GOP nomination race, said. 

"But if I’m running the Trump campaign, particularly as I look towards the vice presidential nomination, I would be trying to figure out anyway I could to reassure the Haley voters that we’re going to listen to them and not just run a base only strategy," he suggested.

Biden also saw a red flag in Tuesday's primaries, as 10% of votes in the Democratic presidential contest in Maryland were "uncommitted," according to unofficial and incomplete tabulations. It's the latest example of far left voters expressing their dissatisfaction with the president's Mideast policies.

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The primaries were held on the eve of a proposal by Biden and his re-election campaign to hold presidential debates with Trump in June and early September - with a vice presidential debate over the summer - to which Trump quickly agreed.

Mark Penn, the longtime Democratic pollster, former top political adviser to former President Bill Clinton and former Secretary of State Hillary Clinton, and Fox News contributor, pointed to Biden's anemic poll numbers in the key battleground states as he argued the president's debate proposal came out of weakness.

"You don’t want to debate when you’re ahead. You want to avoid debates at all costs," Penn said in an interview on Fox News' "America's Newsroom." "Obviously it’s uphill for President Biden, or he wouldn't be debating in the first place."

National surveys for months have indicated that many Americans are anything but thrilled with the rematch between the 81-year-old Democratic incumbent and his 77-year-old predecessor in the White House.

"You’re going to put the most unpopular politicians we’ve ever seen run against each other in front of 80 million people on a debate stage. One of them is famously bombastic and toxic and loose with the facts. The other one is barely able to get out a sentence. He had six jump cuts in a 13-second video they put out today," Kochel said as he pointed to Trump and specifically to Biden's video proposing the debates. 

And Kochel predicted that the debates may "reinforce to the country how dissatisfied they are with these choices."

Get the latest updates from the 2024 campaign trail, exclusive interviews and more at our Fox News Digital election hub.