It was a rough week for No Labels, the influential centrist group that’s been working for over a year towards launching a bipartisan, third-party 2024 presidential ticket.

Hours after former New Jersey governor and two-time Republican White House contender Chris Christie announced he wouldn’t join the No Labels so-called ‘unity’ ticket, their most well-known champion died.

The group suffered a major loss with the death of former longtime Sen. Joe Lieberman, the Democratic Party’s 2000 vice presidential nominee and a 2004 presidential candidate who later became an independent and was a No Labels founding co-chair.

In public, Lieberman was a tireless defender of the group’s push for a third-party ticket. And privately, he was a key player in No Labels’ recruitment efforts.

Lieberman also repeatedly emphasized that Americans were anything but enthused about a 2024 rematch between President Biden and former President Donald Trump, and he regularly pushed back against warnings from Democrats that a No Labels ticket would pave a path to victory for Trump in November.

‘That’s not our goal here,’ Lieberman told Fox News Digital late last year. ‘We’re not about electing either President Trump or President Biden.’

Hours before Lieberman’s death, Christie became the latest high-profile politician to decline to join a 2024 No Labels ticket, along with fellow Republicans in former Maryland Gov. Larry Hogan and Georgia Gov. Brian Kemp, and moderate Democratic Sen. Joe Manchin of West Virginia.

There was also plenty of speculation that former U.N. ambassador and former South Carolina Gov. Nikki Haley, who was the final 2024 GOP presidential nomination rival to Trump before she ended her White House run earlier this month, would consider running on a No Labels ticket. No Labels had expressed interest in her earlier this year.

But Haley repeatedly nixed joining a No Labels ticket, most recently in an interview on ‘FOX and Friends.’

Christie, a vocal GOP critic of Trump who made his opposition to the former president the centerpiece of his unsuccessful 2024 campaign, said in a statement that ‘while I believe this is a conversation that needs to be had with the American people, I also believe that if there is not a pathway to win and if my candidacy in any way, shape or form would help Donald Trump become president again, then it is not the way forward.’

As Christie looked into the possibility of joining a No Labels third-party ticket in recent weeks, sources confirmed to Fox News he commissioned polling before deciding against the move. 

New Hampshire Gov. Chris Sununu, another vocal GOP critic of Trump, was also courted. No Labels repeatedly reached out to Sununu and indicated in conversations that he was one of their top choices based on focus group data, a source familiar with those conversations confirmed to Fox News. 

‘The Governor politely entertained their appeals, and indicated at numerous stages throughout the conversations that he had no interest in serving on their ticket. They reached out again at the beginning of March, and he once again told them no,’ the source said.

Longtime Republican strategist and communicator Ryan Williams said that much of the hesitancy appears to be ‘a great concern that a third-party run on any ticket could help Trump. If you don’t like Trump, you don’t want to help him.’

And Williams, a veteran of multiple GOP presidential campaigns, noted that running for president is a massive endeavor which ‘takes up much of your life. Without a clear path at this point for a third-party candidate, that’s a big sacrifice to make.’

Complicating No Labels efforts is independent presidential candidate Robert F. Kennedy, Jr. The longtime environmental activist and high-profile vaccine skeptic who is the scion of the nation’s most storied political dynasty is grabbing plenty of attention as he polls higher than any other third-party White House contender since Ross Perot over three decades ago.

Despite setbacks this week, No Labels continues its mission of obtaining ballot access across the country. Hours before word of Lieberman’s death, the group announced that it has officially qualified for the ballot in 19 states.

Lieberman, in announcing earlier this month the formation of a committee to vet contenders for the potential bipartisan ticket, wrote that ‘if we find two candidates that meet our high threshold, we will recommend that ticket to No Labels’ delegates for a nomination vote at a National Nominating Convention that will be held later this spring.’

But he acknowledged that ‘if No Labels is unable to find candidates who meet this high threshold, then we simply will not offer our ballot line to anyone.’