In Iowa politics, swine sells.

Joni Ernst, an Iowa state senator who appears poised to win the most votes in her party's U.S. Senate primary Tuesday, has crisscrossed Iowa during the past weeks in an RV bearing an only-in-the-heartland collage: camouflage, an American flag, picturesque farmland, a pig's face and the words, “Honk if you want to make D.C. squeal!”

That tagline invokes Ernst’s debut television advertisement that went viral on the Internet, with more than half a million views on YouTube, and launched her from a little-known candidate in a second-tier Senate race to a name in the national political conversation — and, now, a likely Republican nominee for Senate.

“I grew up castrating hogs on an Iowa farm,” Ernst says, grinning, in the ad, released in March and aptly titled “Squeal.” “So, when I get to Washington, I’ll know how to cut pork.”

Her campaign has followed up that instant classic with ads focusing on other parts of her biography and personality: “Shot,” in which Ernst, a lieutenant colonel in the Iowa National Guard, rides a motorcycle and shoots a handgun, and “Long Way,” a more traditional ad shot on her family's farm and in her hometown of Red Oak, Iowa.

“It’s a long way from Red Oak to Washington,” she says in the latter ad, “but I’ll take our values there, instead of the other way around.”

Strategists from both parties have praised the ads as inventive and, for Ernst, game-changing. “They're memorable, they're catchy,” said one Democratic strategist. “I don't think anyone will deny that."

In an open letter that otherwise expressed concerns about Ernst, Steve Deace, an Iowa-based conservative radio host, called the “Squeal” spot “the best political ad I’ve seen in Iowa during my time in statewide politics.”

Her recognizable brand has elevated Ernst in most polls above the rest of the Republican primary field. But now, as the focus shifts to a general election contest against Rep. Bruce Braley, a Democrat and the slight favorite, the question is: Will Ernst be able to transition beyond a memorable caricature to a competitive, multidimensional candidate?

"When you look at her record, it's pretty thin,” said Sam Lau, a spokesman for the Iowa Democratic Party. “Once you get past the ads, what's going to be left of Joni Ernst?"

The answer will hinge in no small part on the next moves by Todd Harris, the wizard behind Sen. Marco Rubio's big-picture political strategy, and his colleagues at Something Else Strategies, the creative force behind Ernst from the beginning. For Harris and his firm, a string of buzzy ads was exactly the plan for Ernst, who needed to quickly increase her name recognition -- and had a unique biography with which to do it.

“So many political ads are just a litany of poll-tested bullet points, and we've done our share of those as well,” Harris said. “But when you're trying to introduce a candidate for the first time, you really do want to try to tell their story and give people a real sense of who they are. Marco was able to do that in his campaign, and our goal with Joni is to do the same.”

Ernst’s first impression has been robust enough to help her overcome a significant cash disadvantage relative to her main Republican rival, Mark Jacobs, a multimillionaire.

Her notoriety also has attracted big-name endorsements from Mitt Romney and Rubio, who have appeared in television advertisements by outside groups affirming their support. And, on the opposite side of the Republican spectrum, Ernst won backing from Sarah Palin, who appeared with her on the campaign trail -- and who, as a telegenic, charismatic Republican woman, has engendered comparisons to Ernst, both positive and negative.

“They're both straight-talking conservative women, but beyond that no one should ever try to be another Sarah Palin because she's one-of-a-kind,” Harris said. “Joni Ernst is running on who she is.”

“Comparisons like that, we knew they'd be inevitable. But we're not done telling Joni's story,” Harris said. “By the time the campaign is over, people will have a more complete picture.”

Ernst’s campaign will not be over Tuesday, when she is expected at least to be the top vote-getter among the Republican field, and stands a good chance of winning the primary outright. Ernst will need to win at least 35 percent of the vote to avoid a run-off, which would be settled among party activists at a convention in a few weeks. Most recent public polls show Ernst surpassing that threshold.

Before the votes were even counted, Braley’s campaign was preparing to face Ernst head-on — and, true to the campaign so far, Ernst’s ads were front-and-center.

“While Sen. Ernst courted voters with motorcycles, pistols and barnyard metaphors intended to position her as a different kind of politician, just beneath the surface a typical politician was at work,” Sarah Benzing, Braley’s campaign manager, wrote in a memo distributed to press Tuesday.

Benzing added, “Joni Ernst has made her job in the general election harder by manufacturing an Image she cannot live up to.”