TV is not Hillary Clinton's friend. And contrary to the conventional wisdom on what it takes to win the White House, her best media course between now and November is to avoid it as much as possible if she wants to be the first female president of the United States.

That's not going to be easy, though, as her opponent, Donald Trump, one of the most adroit TV candidates in the history of the medium, is sure to be all over the tube, constantly calling her out.

Clinton is the worst TV candidate since Richard Nixon, and that's saying something, given the uncanny ability of George W. Bush to routinely look like a large animal caught in the headlights and sound as if English was not his first language.

But Bush learned to cope with his media maladies by his second term and started making fun of his own TV failings before others could. In the process, he started to seem almost likable in a sitcom-friendly, crinkly-faced, bumbling-dad kind of way.

Clinton and her advisers have not managed to evolve her TV persona very much for the better in the 25 years that she has been on the main media stage of American life. And her failings on the small screen are directly connected to the core problem of her presidential bid: a widespread perception that she is dishonest.

A CNN poll last week found 68 percent of respondents saying she was not trustworthy and honest. That's the highest on record for her, up 3 percent from earlier in July and 9 percent from May.

Meanwhile, Trump, of PolitiFact “Pants On Fire” infamy, clocked in with 55 percent thinking he is not trustworthy and honest. I know, hard to believe. But a New York Times/CNN poll the week before found similar results.

The numbers should shift a little in Clinton's favor with a post-convention bump this coming week. But you don't undo more than two decades of national TV with four nights of Hollywood celebrities, family members and politicians from your party saying how wonderful you are.

No one, not even the highest-paid consultants, truly understands what happens as a TV camera grabs your image and then pushes it onto millions of screens. After decades of thinking and writing about it, I still marvel at the way the camera loves some and hates others.

But there are some discernible patterns to what works and what doesn't. One involves consistency. The TV illusion that leads to familiarity and, ultimately, trust involves viewers seeing again and again the person they think they know each time they turn on TV — without any unpleasant surprises.

Walter Cronkite, the CBS newsman who was the most trusted TV persona of his era, was essentially the same person virtually every time you turned on TV five days a week — right down to sitting in the same chair at the same anchor desk wearing the same thick-rimmed glasses. And he was always in the same calm, composed emotional range.

When he wasn't in that range, viewers knew it was a life-changing moment, as when he reported the assassination of President John Kennedy in 1963.

It was the same with President Ronald Reagan, a model of consistency in appearance and tone. He was seen in only a few select settings — such as the Oval Office, a state dinner or playing the role of rancher in California — and was almost always in that same steady emotional zone.

Clinton has been the opposite — a million hairstyles, a million wardrobe looks, ever-shifting projections of who she is and how she wants us to think about her. And there have been too many jarring moments, like the one she had at the Benghazi hearing in 2013 when she responded to questions about how the American consulate came under attack with an angry “What difference does it make?”

For those who might want to dismiss this as gender-biased critique, let me add that I believe Barbara Mikulski, Barbara Walters, Margaret Thatcher, Diane Sawyer, Lesley Stahl and Oprah Winfrey have all demonstrated across their public careers the same kind of onscreen consistency that leads to trust.

Clinton's troubled TV image is not news to her handlers. The rollout of her candidacy in 2015 showed how eager they were to find a way other than TV to have her speak to voters. She announced her candidacy in a YouTube video. But the most notable thing about the 21/2-minute video celebrating diversity was that Clinton appeared on screen for only 12 seconds or so.

Even here, the one gesture she is supposed to make — using her right arm to emphasize her hope that viewers will join in on her journey — looks awkward.

Worse for Clinton, on the eve of her video's release that April, “Saturday Night Live” opened with a wicked parody featuring Kate McKinnon, who mocked the ever-shifting Clinton media personas.

The sketch included McKinnon's Clinton warming up vocally for her social media announcement by singing, “Hillary's the granny with a twinkle in her eye. Hillary's the granny and she bakes an apple pie. First female president: Me, me, me, me, me, me me!”

Finally, she looks into her smartphone lens and says in an altogether different, menacing voice: “Citizens, you will elect me. I will be your leader.”

Clinton is at her best on TV when giving speeches or debating — two pre-television staples of political life. She is not great in either, but she's good enough. And I mean that in the same way Barack Obama dismissively referred to her in a 2008 debate by saying she was “likable enough.“

She is at least TV-acceptable in those forums because she focuses on the act of speaking or the conversation of the debate as if she were doing them in a hall. But she can sound inappropriately loud in some TV settings, as if she is yelling in hopes of being heard over an audience.

Thursday night's speech at the Democratic National Convention was representative: solid in terms of delivery for a large hall, but lacking in anything that might be thought of as poetry to match the history of the moment. Worse, it failed to make a dent in the trust issues that dog her.

“I get it that some people just don't know what to make of me,” Clinton said. But she made it sound as if that was the fault of the people who didn't know what to make of her, not hers for not communicating a centered sense of identity and transparency since arriving on the national stage as first lady.

Still, she is better in these forums than she is in more casual TV settings, like late-night talk shows, where the premium is on looking at ease. While Obama thrives in these casual TV settings, Clinton just cannot do jokey and relaxed. Like Nixon, her uptight body language, brittle laughter and downright discomfort make her seem shifty or untrustworthy. Such is the logic of television.

As it stands now, Clinton will have three debates with Trump: Sept. 26, Oct. 9 and Oct. 19.

Trump is superb in most TV settings — particularly those of talk-show cable news, late-night network or news conference, formats that are often live and unscripted, allowing him to improvise, riff and rant as the mood strikes. It's as if he is wired for this kind of live TV.

But he is not so great in debates where homework and preparation can be as important as delivery. The question will be whether Clinton's experience, intelligence, tenacity and preparation will be enough to overcome her disadvantage of competing in a medium where style usually trumps substance.

I can't wait. The primary has taught us much about the changing media landscape as we watched a candidate from the world of television and social media flout rule after rule of political life in winning the Republican nomination.

I wonder if there's another lesson there about the need to be good on television in order to win the White House.

david.zurawik@baltsun.com

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