1) Explanation

Let's break down the sentence to understand the context and the meaning required for the blank:
- "Due to the low voter turnout, reporters described the storm's effect as $\qquad$ to both campaigns."
- The key phrase is "low voter turnout." In an election, low voter turnout is generally considered negative for campaigns, as it means fewer people are voting, which can make it harder to predict outcomes, mobilize support, or achieve desired results.
- Therefore, the blank needs a word that describes a negative effect.

Let's evaluate the given options:
- A. harmful: Causing or likely to cause damage or injury. This fits the idea of a negative effect on campaigns.
- B. benign: Gentle and kind; not harmful in effect. This is the opposite of what's implied by "low voter turnout" in a campaign context.
- C. inconsequential: Not important or significant. While low turnout might be inconsequential in some specific, rare scenarios, it's generally a significant, negative factor for campaigns. The word "harmful" or "damaging" is a more direct fit for the implied impact.
- D. calamitous: Involving or causing sudden and great damage or disaster. This implies a very severe negative effect, which "low voter turnout" could indeed be for a campaign.
- E. deleterious: Causing harm or damage. This is a direct synonym for "harmful" and fits the context of a negative effect on campaigns.
- F. beneficial: Resulting in good; advantageous or helpful. This is the opposite of a negative effect.

Conclusion:

The context of "low voter turnout" strongly suggests a negative impact on campaigns. Both "harmful" and "deleterious" directly convey this negative, damaging effect. "Calamitous" also conveys a negative effect, possibly more severe, but "harmful" and "deleterious" are direct synonyms for each other and fit the general negative impact.

The final answer is $\(\mathrm{A}, \mathrm{E}\)$.