WASHINGTON - U.S. President Joe Biden's team is moving to tap top Democratic allies and even some people once seen as possible rivals as key representatives of his expected re-election bid.

The Democratic National Committee (DNC) will host a "national advisory board" comprised of the sorts of rising-star politicians, including governors J.B. Pritzker of Illinois, Josh Shapiro of Pennsylvania and Phil Murphy of New Jersey, who are known for their own bids for higher office but stayed on the sidelines after Democrats survived the 2022 midterm elections with their Senate majority intact.

The move by White House political officials and other allies to sign on high-profile spokespeople, which is typical for parties moving into the frenzy of campaign season, shows Biden is headed towards a formal re-election announcement now expected in April, though the date could slip, sources familiar with the situation told Reuters.

Biden's team is making other steps, too, including thinking through possible options for a campaign manager a host city for the 2024 party convention where Biden would be formally nominated. Chicago and Atlanta were seen by Democratic officials as the primary contenders for the convention, which was conducted virtually in 2020 due to the COVID-19 pandemic.

The campaign's strategy is expected to be set by the same inner circle that guided Biden's 2020 race against Republican former President Donald Trump, including his final 2020 campaign manager, Jen O'Malley Dillon.

But that group has struggled to hone a short list of potential campaign managers for 2024 as they look for a trusted operator outside their own ranks who has experience winning a state-wide campaign in a competitive state, among a variety of other qualifications.

"They are looking for a unicorn," said one party adviser.

The new advisory board will be used to demonstrate unity in the party behind the candidate, traveling the country for campaign appearances and doing interviews on television on behalf the party and, eventually, the candidate. News that the group was being assembled was first reported by the Washington Post.

Biden, who turned 80 in November, is the oldest president to hold office. Recent polls show aging leaders are a concern for Americans in general, and Biden's age in particular worries Democratic voters. But the president's aides are shrugging off polls showing doubts about his age as irrelevant at this stage of the race.

No major rivals for Biden have emerged on the Democratic side, though the self-help guru Marianne Williamson is expected to formally announce on Saturday that she is mounting a long-shot bid in the primary after doing so in the more crowded field from which Biden emerged victorious in 2020.

On the Republican side, Trump is seeking a second term, and a set of would-be challengers are laying the groundwork for their campaigns.

In the absence of a formal re-election announcement, the White House continues to book Biden in campaign-style appearances across the country. On Monday, Biden is expected to speak to the International Association of Fire Fighters, the first major labor group to endorse him ahead of the 2020 campaign.

Biden's public approval rating was just 41% in a Reuters/Ipsos opinion poll last month. That is close to the lowest level of his presidency, though similar to where Trump was at the same time in his administration.

(Reporting by Jarrett Renshaw and Trevor Hunnicutt;)