How Joni Ernst’s ad about castrating hogs drove the news and her poll numbers

Iowa state Sen. Joni Ernst is running for the U.S. Senate. (Dan Balz/The Washington Post)

The Post’s Philip Rucker and Dan Balz reported on the Iowa Senate race and how Republican candidate Joni Ernst was able to vault herself to prominence with her catchy ad “Squeal.”

Rucker and Balz wrote:

At a time when voters tune out many political messages, the ad was a vivid reminder of the enduring power of a single image. In the first three days, her 30-second spot was viewed nearly 400,000 times on YouTube and became the talk of cable news, catapulting the state senator from rural Red Oak into the top tier.

This is a familiar story in primary elections.  As Lynn Vavreck and I document in “The Gamble,” the 2012 Republican primary election showed this pattern over and over. A single event helped an underdog candidate catch attention of political observers and reporters, who then devoted much more coverage to that candidate.  The candidate’s poll numbers increased as a consequence.

The same thing is true for Joni Ernst.  Here is a graph of news media mentions of her, based on data from General Sentiment.

Ernst declared her candidacy in July 2013 but received relatively little attention for many months, except for the day she was endorsed by Mitt Romney.

However, the day the “Squeal” ad first aired, Ernst got more media coverage than she had received before or has received since.  The ad appears to have helped her receive consistently more news coverage these past two months.  The endorsement of the Senate Conservatives Fund and the release of a second ad entitled “Shot” have also garnered attention.

The small number of polls in the Republican primary don’t allow strong conclusions about the impact of “Squeal” and subsequent news coverage.  But consider this: In three polls from February, Ernst averaged about 11 percent.  In the four polls in April, she averaged 25 percent.

All of this is in line with Rucker’s and Balz’s reporting.  It also shows that a pattern evident in many previous primary elections seems to have repeated itself here.  Now the question is whether Ernst’s momentum will carry her to victory on June 3.