I Approve This Message. Now, Remember Your Secrecy Envelope.

Welcome to On Politics. I’m Nick Corasaniti, your host on Tuesdays for coverage of all things media and messaging. I’m writing from Philadelphia, where I’ve moved for the rest of the race and have subsisted largely on the true Philadelphia sandwich: the roast pork, provolone and broccoli rabe!

The disclaimer was familiar to any Pennsylvania voter who has suffered through a commercial break this fall — “I’m Joe Biden, and I approve this message” — but the ad that had preceded it took no shots at President Trump’s leadership, nor did it offer any testament to Mr. Biden’s middle-class bona fides.

Instead, a blue outline of the state of Pennsylvania appeared onscreen, and a narrator calmly walked through the importance of making sure anyone voting by mail correctly used the secrecy envelope.

With just a week left to go in a multibillion-dollar political advertising season, campaigns have begun using their paid media operations to augment their get-out-the-vote efforts. Like so much else in 2020, it’s a shift from the norm: Traditionally, campaigns rely on their on-the-ground field teams, not their TV ads, to try to get voters to the polls.

But a few unique elements of this election are making get-out-the-vote ads a necessary expenditure. First and foremost, in the middle of a pandemic, field operations cannot knock on doors and offer rides to voting locations at the scale necessary for a modern campaign.

And with the electorate increasingly polarized, any closing-argument advertisements seeking to persuade undecided voters are fighting over a relatively small audience.

“There just aren’t that many persuadable targets,” said Michael Beach, a Republican ad strategist. “Even in TV ads, early vote was mentioned in a lot of those ads, and traditionally that wouldn’t have been the case.”

With so many people voting by mail this year, campaigns have new opportunities to keep tabs on voters through the steps of the process — sending voters targeted ads encouraging them to request ballots, then following up with more ads prodding them to return those ballots.

Most “ballot chase” programs, as they’re called, are run online, often through Facebook. Since many states offer data on who has requested a ballot and who has returned one, campaigns can target ads directly to those voters on Facebook. Once a voter returns a ballot, campaigns can remove that person from their target list and not waste any money on a vote already cast.

“We can target you every step of the way,” Richard Walters, the chief of staff of the Republican National Committee, told me earlier this month. “We know when you requested the ballot, and we know to continue following up with you until your ballot has been returned, and until we can see it has been returned.”

Digital ballot chase programs, while not entirely new, are being vastly expanded this election cycle. The Trump and Biden campaigns have dozens of ads telling voters to “Secure your ballot the safe way today!” and warning that “Time is running out to return your ballot!” (The Biden campaign even highlighted its ballot chase program in a fund-raising pitch.)

While television ads cannot be targeted with the same precision, some advancements in data analysis have allowed for more focused pitches. Mr. Beach, through his company Cross Screen Media, compiled lists of likely early voters and swing voters in three major battleground-state markets: Detroit, Phoenix and Charlotte, N.C. His team found that early voters tended to be older and watched a lot of cable and local news broadcasts, which are traditionally more expensive political advertising spaces.

But when audiences who are presumed to have voted early were removed from the lists, the landscape changed dramatically: ESPN, E! and Comedy Central became the most popular channels among swing voters in those three markets who most likely hadn’t voted yet.

So, maybe “SportsCenter” viewers can expect to see more ads with state-specific ballot instructions. But the more traditional ad wars are not letting up. The TV in the background of my Philadelphia apartment just blared that Mr. Biden “would be a president for all Americans” as I wrote this last sentence.

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Ad of the week: Tough guy

There are few characteristics more important to Mr. Trump than maintaining an appearance of toughness. The Biden campaign has enlisted the help of Dave Bautista, the 6-foot-6 former professional wrestler turned Hollywood actor, to cut into that narrative in a new ad.

The message: Mr. Bautista opens the ad with a flex and a yell. Then he draws a distinction between Mr. Trump and Mr. Biden: “It’s easy to lie to people; it’s easy to bully people,” he says. “That does not make you a tough guy. It’s easy to tell someone what they want to hear. It’s not easy to tell someone what they need to hear.”

As a map shows coronavirus cases increasing across the country, Mr. Bautista says that what America needs is “someone who’s going to have a plan, so we can get back on track.” The ad ends with Mr. Bautista circling back to the concept of toughness, praising Mr. Biden as a leader who is “stepping back into this fight for Americans.”

The takeaway: Professional wrestling is a popular form of entertainment among white men, a constituency among whom Mr. Biden consistently trails Mr. Trump, and a testimonial from one of World Wrestling Entertainment’s legends is clearly aimed at that audience. But the ad also comes as the Biden campaign has been avoiding an emphasis on negative messaging, with 40 percent of its ads wholly positive.

The criticism from Mr. Bautista in the beginning, cutting at Mr. Trump’s proud claims of toughness, borrows a bit from previous negative ads from groups like the Lincoln Project that both criticized the president and sought to get under his skin.

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