In January 2016, three political advertisement cracked the top 10 most-viewed YouTube ads. It was the first time any political ad cracked the list. (Jhaan Elker/The Washington Post)

In the years since Sarah Palin’s sound bites and the “Obama girl” cemented 2008 as America’s first “YouTube election,” the world’s most popular video site has proven even more spellbinding — and powerful — than political campaigns ever imagined.

In January, a political ad — actually, three — ranked among YouTube's 10 most-watched ads for the first time in history, delivering millions more views to campaigns than to the best commercials corporate America had to offer.

And in the early caucus and primary states of Iowa, New Hampshire, South Carolina and Nevada, the streaming giant's open pool of reserved ad time did something it had never done: It sold out, a sign that candidates yearned so deeply to reach voters’ cell phones that they wanted to snatch up every YouTube second money could buy.

Google’s video giant has become not just the Web's biggest petri dish for the funny, weird and astronomically popular. With its 1 billion viewers and cultural omnipresence, it now offers campaigns a breadth no hometown TV network can match.

"Anybody at this point who doesn’t get it’s a part of everyday life ... is myopic at best and malpracticed at worst," said Chris Wilson, founder of WPA Opinion Research and the director of research and analytics for the Ted Cruz campaign, whose border-jumping "Invasion" ad ranked among January's most-watched.

YouTube and digital advertising have played key roles in past campaigns, Wilson said, but "this is the first cycle where if you’re not doing it, you're going to lose."

Republican front-runner Donald Trump has been the most digitally prolific, with more YouTube views and videos about his campaign than all other candidates, data provided by Google show. Bernie Sanders, Hillary Clinton and Cruz follow, in that order, closely resembling the real-life race.

But YouTube's digital populism — hundreds of millions of hours are watched every day — ensures no campaign is ever in complete control. Trump's presidential announcement garnered 1.8 million YouTube views — impressive, but less than videos in which he is thwapped by a bald eagle, exalted by young "Freedom Girls" and ridiculed for 18 minutes of "idiotic moments."

Even as Facebook and other competitors have vied for video content, YouTube's audience remains widespread: More 18-to-49-year-olds watch its videos on their phone than tune into any cable network in America, Nielsen data show.

But YouTube is far from a young person's playground: Google says its surveys have found that more than half of baby boomers and seniors are watching online videos, too. When the site recently unveiled a program offering advertisers first grabs at premium ad time, the first to sign up was AARP, the powerful seniors' advocacy group long known for political-ad blitzes on TV.

In an encouraging sign for campaign ad makers — and a reflection of how bizarre or amusing this race has become — many viewers are seeking out the same political ads they only previously endured during commercial breaks. Since April 2015, Google data show, Americans have watched 12,500 years' worth (110 million hours) of YouTube videos about the 2016 issues and candidates.

For this year's presidential race, data from market researcher Borrell Associates show, campaigns will spend nearly $300 million on online ads — more than they'll spend on newspaper and radio ads, combined.

Though broadcast TV remains king, gobbling up $2 billion of ad budgets, campaigns are increasingly turning to YouTube for its finer precision in targeting voters and its potentially viral popularity. Old-fashioned commercials are pricey, time-limited and impossible to pass on, while YouTube lets campaigns experiment with a wider range of lengths, costs and talking points.

The record-setting YouTube ads from January are vastly different in target and tone. Cruz's satirical ad depicted lawyers and bankers crossing the Rio Grande in suits and heels; another, from an anti-Donald Trump super PAC, replayed past interviews during which the conservative firebrand praised Clinton and contradicted his current ideals.

But the most popular, with nearly 3 million views that month, featured no mudslinging, and came from the Sanders' campaign: A tear-jerking spot set to Simon and Garfunkel, in which the candidate tours the American heartland. “Well I've hit replay about 10 times now," a YouTube commenter wrote. "Anyone else?”

In 2004, before YouTube, presidential players' online-ad budgets were less than 1 percent what they spent on TV, and their digital work was almost always designed to solicit donations, not to share talking points, endorsements or upcoming events. Campaigns also had no central landing site to spend their cash: The George W. Bush campaign's biggest digital ad buys included a Spanish-language news site in Miami and the home page of Parents magazine.

A year later, YouTube premiered its first video — "Me at the zoo," a shaky, sophomoric joke about the length of an elephant's trunk — and campaigns began to see the potential of social media that could spread their messages with unprecedented speed. In a 2007 YouTube interview, then-Sen. Barack Obama likened the service to President Franklin D. Roosevelt's groundbreaking radio speeches, pledging “21st century fireside chats where I’m speaking directly to the American people via video streams."

Today's YouTube has made that race look like the Internet in its infancy. Sanders' "America" ad was watched more in a month than Obama's candidacy announcement ("My Plans for 2008") has been watched in nine years. And campaigns that even in 2012 were simply slapping their TV ads online are now going to studios to make vibrant, bite-size videos designed explicitly for the Web.

YouTube now staffs two advertising teams, for Republicans and Democrats, led by veteran political operatives and staffed with former campaign workers who will often travel to candidates' headquarters to improve ad campaigns and seal deals. The company would not say how large those teams are, but said they were similar in size to YouTube teams working with Fortune 500 conglomerates.


A still from the Ted Cruz campaign's "Invasion" ad. In January, it became one of the first political spots to ever top YouTube's most-watched ads. (YouTube)

"When we've heard the 'YouTube election,' it was when campaigns were experimenting with the technology for the first time,"  said Charles Scrase, YouTube's industry director for government and advocacy. "But there's been a massive shift in ... how the traditional political mind chooses to advertise online."

Web video's wide-open nature has changed how candidates choose to extol their moments of triumph. After Erica Garner — the oldest daughter of Eric Garner, whose death by New York police rallied Black Lives Matter protests — praised Sanders, his campaign dispatched a crew to record her for a four-minute, cinema-quality endorsement, which they ran on YouTube uncut before reaching out to the networks.

But it has also allowed campaigns to test out angles that could pack greater punch than on TV. During the holidays, Cruz's camp shared a YouTube parody ad — with books such as “How Obamacare Stole Christmas” and “The Grinch Who Lost Her Emails” — that became its most popular spot yet, with nearly 2 million views.

Campaigns frustrated with Trump's cable-TV dominance have even turned to their own YouTube channels for unlimited airtime on friendly turf: In one Cruz YouTube spot, kids play with a Trump action figure whose powers include pretending to be a Republican.

"Politicians go where the eyeballs are," said Steve Grove, director of Google's News Lab, and "video is unique in the social media realm: It's sight, it's sound, it's a ... strong way to convince people that your view is the right one."

The streaming service's planet-spanning reach has helped further spread this election cycle across the world. Data provided by Google shows that, outside of the U.S., Mexico leads the world in viewership for Trump and Rubio videos, likely due to their views on immigration. Canada leads for Cruz, the country's native son.

But YouTube has also, with help from the broader social-media sweep, given the race a flare and urgency perfectly attuned to what Utah Gov. Gary R. Herbert this month called modern politics' “reality-TV voyeurism." What came first: The colorful, excitable chaos of our electoral spectacle — or the technology precisely coded to stream, share and multiply it across the globe?

"You watch these pundits on TV? That’s my grandfather’s medium. I’m not watching that. I'll watch it the next day on YouTube," said Carmen Villafañe, a director at Complex, the youth-culture magazine and digital platform that now delivers debate coverage and interviews from the campaign trail straight to its 1.2 million YouTube subscribers. "The fact is that these candidates have become memes, and if it's one thing that our audience loves, it's memes."

Broadcasting straight to YouTube, she added, was like "fishing where the fish are. That’s where these kids are picking up their information, and they'll sit there and refresh, refresh, refresh."

YouTube's greatest power may not be its ability to entertain fans, but in reaching voters who least expect it. Kevin Lepore, a 28-year-old analyst living outside Chicago, was scrolling through his phone one morning on the train ride to work when he stopped abruptly on Sanders' "America" ad and, surprising himself, started tearing up.

A scant TV watcher, Lepore had seen few traditional campaign ads. But upon watching it, he decided to share the video on Facebook with his mother-in-law in Iowa, telling her to "please consider" Sanders. More than a hundred people liked his comment, with one stranger writing, "come on Bonita!! We need you!!"

"In the old days," Lepore said, "you'd have only see it from, you know, 6 to 9 p.m., whenever you're watching TV. Now, it's everywhere."