MANCHESTER, New Hampshire — Former President Barack Obama hasn't endorsed anyone in the 2020 Democratic primary, but ads from six White House hopefuls would leave voters with another impression.

Obama, an intensely popular Democratic Party figure, has featured in spots produced by Joe Biden, Michael Bloomberg, Tulsi Gabbard, Deval Patrick, Tom Steyer, and Elizabeth Warren — Biden, Bloomberg, and Warren, in particular, using snippets of speeches he's given about them to give the appearance he's narrating the ad.

Obama's silence, seen by many as a snub of Biden, his two-term vice president, has left open the possibility that the remaining top contenders could become the heir apparent to his legacy and coalition, with various prospects of success.

Biden has been the most determined to compensate for Obama's reticence to weigh in on the race, insisting repeatedly that he asked his old boss to remain neutral because he wanted “to win” the nomination on his "own merits."

Yet Biden, 77, mentions his “buddy Barack” constantly on the campaign trail, has pushed ads voiced over by his former running mate, and has even floated Michelle Obama as a potential No. 2 on his own ticket.

This isn't just about who I am, this is about who we are as a country. We're tough, resilient, but always full of hope. With every fiber in my being, I believe there’s not a single thing we can't do—if we do it together. pic.twitter.com/GfPWX1VTvH — Joe Biden (Text Join to 30330) (@JoeBiden) January 17, 2020

Then, this week, as he ramped up his attacks on surging Bernie Sanders, 78, and Pete Buttigieg, 38, on the back of their one-two tight finish in Iowa, Biden challenged the former mayor of South Bend, Indiana, to criticize Obama directly.

"Mayor Pete likes to call me part of the old failed Washington. Was it a failure when I helped pass Obamacare, the Paris Agreement, the Violence Against Women Act, or the assault weapons ban?" the 36-year senator tweeted.

As the nominating process has progressed, concerns about Biden’s ability to beat President Trump in November have grown, and Michael Bloomberg, 77, and Deval Patrick, 63, have been leveraging the nerves as an excuse to launch last-minute White House bids. Even John Kerry, 76, a high-profile Biden supporter who is campaigning for him across the country, last week was overheard in an Iowa hotel discussing whether to announce his own second stab at the presidency.

A slow drip of Obamaworld endorsements stoked rumors of the 44th president’s worries about Biden’s third-time candidacy, encouraging reports that he told Biden he didn’t “have to” vie for the 2020 nomination, that he conveyed to a rival contender that Biden “doesn’t really have it any more,” and another that he was leaning on donors to contribute to Warren.

Despite earning the praise of former two-term Democratic Iowa governor and Obama Secretary of Agriculture Tom Vilsack and the tacit approval of Jim Messina, Obama's 2012 campaign manager, his opponents, sensing an opening, are jostling harder to position themselves as Obama’s predecessor after Hillary Clinton, with and without ads.

Ahead of Iowa's kickoff caucuses on Monday, Buttigieg evoked Obama’s vision of “hope and change” at the Iowa Democratic Party’s Liberty and Justice Celebration, recalling his first trip to the state to knock “on doors in rural Iowa for a different young presidential candidate with a funny name.”

Warren, 70, however, upped the ante. This month, she released two ads, one before the first-in-the-nation contest that included Obama's image and another ahead of next week's New Hampshire primary in which he can be heard touting her work in setting up the Consumer Financial Protection Bureau under his administration via audio from a 2010 Rose Garden address.

“Elizabeth understands what I strongly believe: that a strong, growing economy begins with a strong and thriving middle class,” Obama says of the now-Massachusetts senator.

People told me the CFPB could never happen, but it did. I was proud to fight alongside President @BarackObama for middle-class families. I know how to fight—and I know how to win. pic.twitter.com/zYppPvgwtL — Elizabeth Warren (@ewarren) February 5, 2020

Though she and Obama shared a rocky relationship during his time in office while clashing over their respective ideas for the federal agency, this week, Warren, for example, also embraced his Iran policy during a nationally televised CNN town hall.

Meanwhile, Bloomberg, the billionaire and former mayor of New York City, this week followed Warren's suit, spending $1.2 million on air time for a spot promoting his collaborations with Obama on gun control and education reforms.

“At a time when Washington is divided in old ideological battles, he shows us what can be achieved when we bring people together to seek pragmatic solutions,” Obama says.



President Barack Obama is someone I was proud to call Commander-in-Chief, and someone I was honored to work with to get big things done.



I miss that feeling. pic.twitter.com/CNUWTzXtcU — Mike Bloomberg (@MikeBloomberg) February 5, 2020

But at a Warren rally in Derry this week, New Hampshire voters suggested Bloomberg and Warren were wasting their money.

For Bruce MacIver, 59, Buttigieg was in a better place to take up Obama's mantle.

"It seems like he’s for the people, and even though he’s not a carbon copy of Obama, he’s got some fresh ideas of his own, but he’s going to be looking at what Obama’s already established and probably will continue to support a lot of that stuff,” the Salem auditor told the Washington Examiner.

Debbie Lane, 60, similarly thought Warren’s efforts were in vain.

“No, I don’t read her that way,” the Hudson teacher said, adding Buttigieg would likely beat her to Obama's endorsement. “He just has some energy. He gets people motivated. Even though he doesn’t have the experience that some of the other candidates have, he’s really able to motivate people a lot easier than the other candidates.”