Like it or not, it's news in modern-day campaigning when a candidate in a tight race avoids personal attacks. Which is why Democrat Stacey Abrams' approach to the race against Republican Brian Kemp raised so many eyebrows.

While Kemp is pummeling her with attacks labeling her a "radical" puppet of California interests, Abrams is so far avoiding any direct response. It's such an unconventional move, she's attracted statewide and national attention for that strategy.

An Emory University study released in June helps explain why. While viewers may rightly claim to be annoyed by the ads, the research showed that negative advertising from a candidate is more effective than positive spots in mobilizing voters.

It concluded that every 1 percent increase in negative advertising by the candidate produces a “significant” lift in the candidate’s share of the vote. It also found that negative ads from the candidates are approximately twice as effective as attack ads from political action committees.

Which is to say, don’t expect the attack ads to let up this fall.

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