Democrat Beto O'Rourke has spent more on Facebook ads than President Donald Trump

WASHINGTON – Beto O'Rourke, the Democrat trying to knock off Texas Sen. Ted Cruz with a social media-fueled campaign, has spent more money on Facebook ads since June than President Donald Trump, according to figures released Thursday by the Wesleyan Media Project.

Trump edges out O'Rourke when digital ads on Google are included, spending a combined $5.8 million on digital ads through mid-October compared with O'Rourke's $5.6 million. 

Still, nearly one-third of O'Rourke's television and digital ad dollars for his Senate campaign have gone to the internet.

That may not be surprising for a candidate who live-streams his burger runs.

More intriguing may be why Sens. Elizabeth Warren of Massachusetts and Kristen Gillibrand of New York rank just behind O'Rourke in digital ad spending among Senate candidates this year. 

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Both Warren and Gillibrand are expected to cruise to re-election in their heavily Democratic states.

But both are also potential 2020 presidential candidates. And less than 10 percent of their Facebook ad spending was in their home states. That suggests Warren and Gillibrand are more focused on building an email list and raising money in preparation for a presidential run than in running for re-election, according to the Wesleyan Media Project report.

Warren spent about $1.6 million on digital advertising, and Gillibrand spent $937,200, from May 31 through Oct. 15.

California Sen. Kamala Harris, who is not up for re-election this year but is another potential 2020 contender, was close behind with $857,600.

Vermont Sen. Bernie Sanders, who has not ruled out another presidential bid, spent $369,500. Sanders faces token opposition for re-election in Vermont, where 1 percent of his Facebook spending was targeted.