The former West Virginia governor, first elected to the U.S. Senate in 2010, will speak to the "No Labels" organization promoting the possibility of backing a third-party candidate.

Manchin, 75, is arguably the most conservative Democratic senator. He has told reporters that he will wait until late this year before announcing whether he will seek re-election to his U.S. Senate seat representing West Virginia.

Should Manchin seek another term, he would likely face a serious challenge from Governor Jim Justice who is seeking the Republican Party nomination in the Senate race. The state has been leaning heavily Republican, having overwhelmingly voted for Donald Trump in 2016 and 2020.

Meanwhile, Manchin has not swatted away reporters' questions over whether he might consider what would be a long-shot run for the White House as an independent candidate.

"It is clear that most Americans are exceedingly frustrated by the growing divide in our political parties and toxic political rhetoric from our elected leaders," Manchin said in a No Labels statement last week detailing Monday's town hall event at Saint Anselm College in Manchester.

Trump, a 77-year-old former president, leads a crowded field of Republican presidential aspirants and many voters express worries about 80-year-old President Joe Biden seeking a second term. But speculation of an independent candidate entering the race generates heartburn among Democratic strategists who want the incumbent re-elected.

Opinion polling shows that neither Democrats nor Republicans are thrilled with their likeliest 2024 White House candidates, with four in ten Republicans telling a May Reuters/Ipsos poll that they think Trump should not run again in 2024, and a similar number of Democrats citing a similar view on Biden.

On Sunday, No Labels co-chair Joe Lieberman said his group will not field a candidate in 2024 if polling showed that doing so would help elect the Democratic or Republican presidential nominee.

"We're not in this to be spoilers," Lieberman said in an interview with ABC's "This Week" program.

With more than a decade in Congress, Manchin at times has complicated legislative initiatives being pushed by his party leaders. But Democratic leaders have treaded softly as Manchin also has been key to the party holding onto its Senate majority.

Since the start of Biden's presidency in 2021, Manchin has done battle over Democrats' drive to expand a child tax credit aimed at raising poor families out of poverty and insisted on relaxed permitting rules for fossil fuel energy projects, which would benefit West Virginia.

That has enraged progressives pushing for government policies encouraging a phasing out of oil, natural gas and coal due to climate concerns.

Democrats hold majority control of the Senate by a narrow 51-49 margin. The 2024 Senate races present the party with an uphill battle to hold that control, given challenging races projected in Montana, Nevada, Ohio, Pennsylvania, West Virginia and other states. The election takes place on Nov. 5, 2024.