People say they can’t stand negative political ads, but studies have shown they can be very effective. And right now, that’s being put to the test in the city of Tampa, with targeted advertising hitting voters’ mailboxes this past week.

“Tampa is one of the greater cities in the United States and I think we try to keep it positive here,” said voter D.J. Johnson.

Johnson, like many Tampa voters, doesn’t typically go for negative advertising. In fact, the political history of the city suggests it may have cost some the election.

“Just address the issues and keep the mudslinging out of it,” suggests voter Randy Babb.

“And you can phrase it in a way of how you can be better for Tampa then someone else, but putting someone down doesn’t make me think better of you,” adds voter Erica Reilly.

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Still, this week, a flier stared circulating in Tampa, hitting mailboxes all over the city. In it, mayoral candidate David Straz criticizes his opponent, former Tampa Police Chief Jane Castor, claiming the front-runner only knows police work and how to spend taxpayer money.

“I say we're telling the truth. And that’s what we were doing,” said Straz, who sees the ads as factual and not necessarily negative.

He also touts his own accomplishments as a successful businessman.

“I think it’s just fine,” said Straz, "because we feel we have to let the voters know exactly what the situation is. And that’s what we’re doing.”

Castor’s campaign, aware of the ad released a statement saying: "Jane Castor has made a point of running a positive and optimistic campaign about her ideas and vision for Tampa. She asked Mr. Straz to do the same and refrain from attacks and negativity too. Unfortunately, he declined."

Political expert Susan MacManus says, generally speaking, negative advertising is heavily criticized, but can be very effective.

“You have to point to some of your opponent’s shortcomings that you think are something that will mobilize people who didn’t vote for you the first time,” said MacManus.

Historically, Tampa has rejected negative campaigns, but in the past decade, the political landscape has shifted, she says.

That’s why MacManus also says campaign consultants around the nation are watching Tampa’s mayoral runoff as a test-case of modern-day voter tolerance.

In short, whatever lessons are learned here, you can expect to see a lot more of more of in the 2020 presidential race.

“Every form of advertising and every messaging strategy that was implemented in this mayor’s race will be carefully combed over by both Democrat and Republican consultants and party activists,” said MacManus.

MacManus says political fliers have become one of the most focused forms of political advertising, targeting the mailboxes of people who meet a particular party or demographic.

It’s possible that Straz might be looking to more-critical advertising because of the amount of ground he would have to make up in order to overcome the lead Castor had in the general election.

Castor took 47.99 percent of the vote in the March 5 primary, compared to Straz's 15.47 percent. Had Castor gotten 50 percent of the vote, there wouldn't have been a need for a runoff.

Voters will have time to judge whether that’s a strategy they embrace or reject with early voting starting April 14 and the runoff election day April 23.

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