Yes and no.
First, it really depends on the mood of the election. As we talked about in class, if people are sick of that kind of stuff, voters will really be turned off by negative campaigning. On the other hand, criticisms can be important in an election to point out inconsistencies and problems with opposing candidates.
Something dubbed a negative campaign may not always necessarily be a negative campaign. There are several different genres of campaigns. A campaign ad may just flat-out smear and rip into a candidate with falsehoods, name-calling, and half-truths. In my opinion, this is the worst kind of negative campaigning as it intentionally misleads and does not even reference the candidate who is paying for the ad--it just rips into the other person.
A second type, one I like to call "two truths and a lie", states some things about the opposing candidate, sometimes true and sometimes false, but then compares those things to the candidate's positions the ad is purporting.
The third type is like the last one, but the ad is actually honest and points out very concerning things an opposing candidate supports, and this is a very important part of politics in that it points out real concerns to voters. It casts a candidate in a light that says "I do not support these positions" and draws clear differences between candidates so voters can decide.
Unfortunately, campaigns are rarely honest, so we are not often exposed to the truth or the whole truth, but pointing out differences between candidates, which I would not call "negative campaigning" is much better than flat out smearing a candidate with falsehoods and lies.
I think negative ads might be more beneficial to candidates who are running against an incumbent. Controversial things will get more free air time for the candidate and more name recognition for the person who is trying to make a name for themselves. Also, campaigns against an incumbent are often dubbed "negative campaigns" because the candidate has political ammunition in the sense that he can point out inconsistencies between policies the incumbent pursued previously and what they are saying on the current campaign trail.