Illinois Republican Mark S. Kirk is the most vulnerable senator in the country up for re-election this cycle. He kicked off his campaign in May with his first television ad, nearly a year and a half from Election Day, and it was promptly treated like a game-changer by some reporters. Of course it’s healthy to digest that kind of analysis with a healthy bite of skepticism.  

https://www.youtube.com/watch?v=fPUoJ70cM4E  

The spot highlighted the senator’s military experience before taking office and his recovery from a stroke he suffered in 2012.  

One reporter described the ad as “great” on Twitter and the Free Beacon declared it  “powerful.” The Washington Post went even further. “This is a fantastic ad from Mark Kirk,” read a Washington Post headline on May 14 .  

“Want to see a terrific political ad? Spend 60 seconds watching the commercial above,” the Post story continued. “That’s moving stuff — whether or not you are a Republican.”  

But it doesn’t matter if the media thinks this ad (or any other ad) is good. The main thing that matters is if voters are indeed “moved” by the commercial. My colleague Stuart Rothenberg made this point last September .  

He wrote:

The purpose of political ads is not to entertain you, make you angry or make you sad. Political ads are not meant to be evaluated as artistic works, though one could, of course, evaluate them that way.

The purpose of a political commercial is to get you to support one candidate and vote for that candidate. (Often, of course, the technique involves discrediting the opponent.) That is, great ads — the “best” ads — create or change vote intentions, or motivate people to vote (or not to vote).

Whether an ad has done that is an empirical question. Yes, it can be a complicated question, given all that is going on in a race at any given time and during any given election cycle. But still, an ad isn’t good because someone likes it — unless that is very explicitly the measure being used.

It will be at least another few days (if not weeks or months) before subsequent polls are conducted and we know if Kirk’s ad was effective in changing the shape of the race.  

Although the $250,000 buy is a significant amount of money, it will be difficult to move enough voters (out of at least 5 million likely to come out next fall), in a large state, a year and a half before the election to stave off Kirk’s vulnerability.  

It’s possible the early ads weren’t meant to change the broader dynamic but to be a public signal to supporters and donors that Kirk is committed to the race and assure them there is a blueprint for how he will confront his physical challenges throughout the course of the campaign. Quantifying the effectiveness of the early ad buy with this intent is more difficult, but still has nothing to do with what reporters think about the commercial.  

What we do know is that early ads can be a sign of significant electoral weakness.  

Last cycle, Arkansas Democrat Mark Pryor was most often regarded as the most vulnerable senator in the country. He aired his first television ad in December 2013 , nearly a year before Election Day. It appeared to be a “moving” ad with the senator holding his Bible and talking about how his faith guided his life and decisions. Democratic strategists believed the ad effectively strengthened the senator’s position. In the end, Pryor lost by 17 points.  

https://www.youtube.com/watch?v=mucYcm6moe0  

But until survey data becomes available out of Illinois, it is premature to think anyone knows the effectiveness of Kirk’s initial ad. Even if subsequent data shows a temporary boost for Kirk, we still regard the senator as a narrow underdog for re-election as a Republican running in a Democratic state in a presidential year. The Rothenberg & Gonzales Political Report /Roll Call rate the race as Toss-Up/Tilt Democratic .  

Related:

Ratings Change: Kirk’s Race Now Tilts to Democrats


Mark Kirk Starts 2016 as an Underdog


Roll Call Race Ratings Map: Ratings for Every House and Senate Race in 2016


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