^{Editor’s note: This story has been updated throughout.}

Underscoring how competitive the race has become between Republican presidential candidates Ted Cruz and Donald Trump, a super PAC supporting Cruz and his campaign each unleashed a round of attack ads Monday hammering the billionaire as out of step with conservatives.

Among the latest salvos was one that came Monday evening from the Cruz campaign, which unveiled a TV ad showcasing the Texas senator’s efforts to tie Trump to “New York values.” The 30-second spot prominently features a 1999 interview in which Trump attributed his liberal stands on some issues, including abortion, to living in the solidly Democratic state.

The commercial also zeroes in on remarks Trump made at a rally in Iowa two months ago, when his poll numbers were beginning to slip in the Hawkeye State.

“And what does Trump think about Iowa?” a narrator asks before an exasperated Trump is shown at the rally, asking his audience, “How stupid are the people of Iowa?”

Set to start airing Tuesday, the ad from the Cruz campaign brings to at least six the number of anti-Trump, pro-Cruz commercials running in Iowa ahead of its first-in-the-nation caucuses on Feb. 1. Cruz’s campaign launched its first negative ad against Trump on Friday, targeting his support for eminent domain. And earlier Monday, a pair of pro-Cruz super PACs launched their first attack ads in the air war.

One of the outside groups, Keep the Promise I, announced it is airing its commercials this week in Iowa and South Carolina as part of a $2.5 million buy. 

By the end of Monday, the super PAC had released three anti-Trump ads. 

Among the commercials from Keep the Promise was one that coins the term “Trumpcare” while comparing the billionaire’s views on health care to those of President Barack Obama and Democratic presidential candidate Hillary Clinton. The 30-second spot is set to air in Iowa through the caucuses and begin running next week in South Carolina.

In another one of the ads from Keep the Promise, Trump is shown in the 1999 interview, which was done with Tim Russert, describing himself as “pro-choice in every respect” and declining to say he would ban “partial-birth abortions.” A 2003 federal law bans that practice, a form of late-term abortion known in medical literature as intact dilation and evacuation. 

“Conservatives and Republicans have a choice: should their nominee hold views more in line with Hillary Clinton or Ronald Reagan?” Kellyanne Conway, president of Keep the Promise I, said in a statement. “Large majorities of Americans — including those that are pro-choice — oppose partial-birth abortion.”

The third ad from Keep the Promise features Trump, who now attacks Cruz on a daily basis, praising the senator at a fundraiser in 2014 in Florida. Keep the Promise I is already running a version of the spot on the Web.

“On Cruz, Trump has gone from self-anointed BFF to critic-in-chief,” Conway said in a separate statement. “The mean and personal attacks on Cruz are at odds with Trump’s praise of Cruz as a ‘a special guy’ and ‘very, very popular.’ Will voters be bullied into believing the bluster, or stick with a brilliant man who won’t betray them?”

Hours after Keep the Promise I unveiled its commercials, another pro-Cruz super PAC, Stand for Truth, released its own anti-Trump ad. Filled with imagery of New York City, the 30-second spot asks viewers if they can really trust Trump and then shows several media appearances in which Trump voices support for liberal views, including the interview with Tim Russert. A spokesman for Stand for Truth did not immediately respond to a request for more information on the ad. 

Trump is also playing offense on the air in Iowa, having launched his own ad Friday portraying Cruz as weak on illegal immigration.

 Learn about The Texas Tribune’s policies, including our partnership with The Trust Project to increase transparency in news.