Former Vice President Joe Biden is dramatically scaling back digital ad buys while his fellow Democratic opponents are ramping up their online presence, a move some strategists say is unusual for a serious political candidate.

Sen. Elizabeth Warren of Massachusetts and other top candidates are outspending Biden online. Biden’s lack of online spending on Facebook and Google ads over the last week come as President Donald Trump continues to throttle him for allegedly pressuring Ukraine to fire a top prosecutor who was looking into a company tied to his son.

Biden has instead shifted his spending toward buying television ads in Iowa, which hasn’t helped his campaign much. Warren, a leading rival for the 2020 nomination, recently surpassed him in a key Iowa poll. (RELATED: Biden Says He Never Discussed Hunter Biden’s Ukraine Deal. Hunter Says He Did)

Democratic strategists are trying to make sense of the decision.

“It’s clear that there’s something in the numbers that’s directing them to go in that direction, and the likeliest explanation is that the rate of return just wasn’t there for Facebook and Google,” Tim Lim, a Democratic digital strategist, told The New York Times Monday. “Which is very, very unusual.”

Others were more critical.

“It is not a good sign for his campaign,” Marne Pike, the chief executive of an unaffiliated Democratic digital strategy, told NYT reporters. “I would have a very hard time imagining noone was searching for Joe Biden and clicking on the ads.”

Biden entered the race in April as one of the contest’s biggest digital advertisers, spending $1.2 million on Facebook and Google out the gate. He ranked 16th among the Democratic presidential candidates for advertising on Facebook, spending only $32,000 leading up to the September debate.

The former vice president has spent only $20,900 on Google during the last six weeks, according to data TheNYT collected. Meanwhile, Warren spent more than 25 times as much, $553,700, during that same period of time.

The Biden campaign says the dwindling digital ad buy is part of a wide strategy designed to take advantage of more traditional fundraising techniques.

“Our campaign invested a robust digital spend early on to build out supporter lists, outspending all other campaigns from our launch through most of the summer,” T.J. Ducklo, a Biden spokesman, told reporters. “By strategically front-loading our investment, we were able to rapidly expand our reach early, instead of meting out our spend over a longer period of time.”

The campaign is planning a “seven-figure” ad buy in the fourth quarter of 2019, according to TheNYT. Gary Coby, the Trump campaign’s digital director, calls the ad buy paltry compared to the money the president pulled in since House Speaker Nancy Pelosi announced an impeachment inquiry.

“$1M for the entire quarter? …we spent $2M+ last week. The year is 2020. If you can’t win on digital, you’re out!” Coby wrote on Twitter Monday morning.

Biden’s campaign has not yet responded to the Daily Caller News Foundation’s request for comment.

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