After weeks of trailing Sen. Ted Cruz in Iowa, the latest polling has Donald Trump back on top in some surveys and trailing just slightly in others.  

While Trump has for some time been attacking Cruz by raising the issue of his Canadian birth, Cruz was awfully slow to punch back. But this is just a microcosm of the way this campaign has generally gone. Despite some pathetic attempts to attack him during debates, amazingly, the GOP front-runner has mostly avoided being attacked by anybody on air—where a message could be honed and delivered without interruption.  

And it’s not just the candidates who have refused to devote any money on this project. According to a recent Huffington Post analysis , a measly $1.71 million has been spent by independent groups” to attack or negatively portray Republican frontrunner Donald Trump.”  (To put it in perspective, Jeb Bush’s SuperPAC is spending about $3 million attacking Marco Rubio in Iowa and South Carolina in just two weeks.  

We keep hearing that the Republican establishment is deathly afraid of Donald Trump, so how come none of them are spending their tens of millions of dollars to try to take him down?  

This feels both stupid and gutless.  

Maybe they are waiting till the 11th hour (a dubious strategy), but there aren’t many anecdotal signs things are going to change.  

Recently, the Washington Post’s Dave Weigel tweeted: “Spent a whole week in Iowa. Saw no ads taking shots at Trump or Cruz. Today’s Iowa Q-poll: Trump 31, Cruz 29.”  

To be sure, campaign ads aren’t working the way they once did. Donald Trump has risen to the top of national polls, despite having spent minimal money. And Jeb Bush (and his SuperPAC) have spent a ton, with nothing to show for it. But this does not mean that ads can’t or don’t work.  

Trump hasn’t needed ads, by virtue of enjoying so much free publicity. And Jeb Bush’s example only proves that money alone can’t make people decide to up and like you. As Yogi Berra said, “If people don’t want to come out to the ballpark, how are you going to stop them?”  

Maybe the days of money buying an election are over, but I seriously doubt the days of negative ads destroying candidates will soon end.  

Of course, it’s important to know the good ads from the bad. As comedian Ron White has said regarding hurricanes, “It’s not that the wind is blowing, it’s what  the wind is blowing.” You can waste a lot of money on bad TV ads that don’t move numbers. And, unfortunately, the guys who create the ads and the ad buyers make a ton of money, whether the ads are good or not.  

That’s why it is crucial campaigns and independent groups test their messages, create compelling ads that are easy to understand and that resonate at an emotional level, fully fund said ads, and then commit to running them in a concerned manner. I can’t be sure that I know what would persuade Republican primary voters to abandon Trump (that’s why you have to test messages), but I am curious what would happen if someone spent a million dollars, say, on an emotionally compelling ad about how Donald Trump cut off medical care to a sick infant—just to get back at his parents. Maybe that would resonate with voters. Who knows?  

You don’t necessarily even have to tug at voters’ heartstrings. Some empirical evidence suggests that spending money on ads could have hurt Trump, even if the ads were solely based on economic policy.  

According to RealClearPolitics’ polling average of Iowa, Trump peaked on Sept. 21 at 28.3 percent, and then began a decline (down to 22.3 percent) into second place by Oct. 6. Since then, however, Trump has rebounded in the state.  

So what happened to cause Trump’s numbers to fall of a cliff in Iowa during that time? Here’s what: The conservative Club for Growth ran ads hitting Trump for his liberal positions.  

That ad buy ran from Sept. 15th to Oct. 5th. So the date of Trump’s polling nadir in the Hawkeye State correlated precisely with the end of the Club’s $1 million ad campaign against him.  

The Club’s second ad focused solely on Trump’s support of eminent domain, a pretty substantive issue. It clearly resonated with some Iowans, and, interestingly, it’s reasonable to assume this issue might resonate even better in New Hampshire—if only someone would fund an ad.  

Matt K. Lewis is author of “Too Dumb to Fail: How the GOP Won Elections by Sacrificing Its Ideas (And How It Can Reclaim Its Conservative Roots).” Follow him on Twitter at @MattKLewis

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