As we were preparing to publish our thorough analysis of the fundraising machine behind Ted Cruz, we noticed something interesting about one of his many, many super PACs: Stand ForTruth, Inc.

What we found we felt was worthy of a separate post and discussion — and it’s not that Stand ForTruth filed with “ForTruth” as one word. Sure, it has caused a continuing nightmare of whether to compromise grammar or accuracy, but the interesting part we found courtesy of Political Ad Sleuth, Sunlight’s tool to make FCC information about political advertising available to the public. These ad filings show evidence of the increasingly bitter campaign brewing between Ted Cruz, alongside his supportive super PACs, and fellow Republican presidential candidate Marco Rubio.

On Monday, Cruz fired longtime spokesman Rick Tyler for distributing a video that falsely showed Marco Rubio criticizing someone reading the Bible. Rubio fired back at Cruz criticizing him for dirty tricks. But we found evidence that the conflict between the two candidates has been brewing for some time.

On Feb. 12, attorneys for the Rubio campaign filed a cease and desist letter with WPDE, a television station in Myrtle Beach, S.C., after a Stand ForTruth ad stated that Rubio supports sanctuary cities which, ironically, was untruthful. Attorneys urged the station to take down the ad due to its lack of veracity. WPDE gave Stand ForTruth a deadline of 5:00 p.m. on Feb. 13 to turn in additional information supporting the accuracy of the ad. It does not appear that the station received any information, and a follow up email included in the public file shows the ads were substituted out by the campaign to a different ad that had already been airing.

The feud continued on Feb. 18, when attorneys for the Rubio campaign sent a second cease and desist letter concerning a second ad placed by Stand ForTruth. This time, attorneys for the pro-Cruz super PAC fired back, calling it “a grave matter, and censoring political speech should be reserved only for instances of false and defamatory content. Neither is present here.” The letter further contends that because Rubio was a member of the “Gang of Eight” and a co-sponsor of immigration legislation which did not address sanctuary cities, the ad is correct.

In this case, an attorney for WPDE wrote back: “Stations may continue to run the ad. Please advise all parties of the decision and place all materials, including a notation of this decision, in your political files.”

But Rubio is not the only candidate to have challenged the actions of the Cruz campaign. Donald Trump has repeatedly condemned the candidate, alleging dirty tricks from running robocalls accusing Trump of not supporting the confederate flag, that Trump would welcome illegal immigrants into the U.S. as citizens and allegations that Cruz staff members told voters caucusing in Iowa that Ben Carson was dropping out. (Carson and Cruz reportedly had a secret meeting to discuss the animosity between the two campaigns over the issue.) The Cruz camp, on the other hand, has denied campaigning dirty.

However, it’s important to note that Cruz has more super PACs supporting him than any other candidate. Super PACs are prohibited from coordinating directly with the candidates, but they are allowed to raise unlimited funds to support or oppose a candidate. In years past, a super PAC has performed some of the “dirty work” of the campaign — saying the things that the candidate didn’t want to say or be associated with in the campaign. (Of course, all of that has changed in a Trump-running-for-president-world.)

Most candidates only have one or two super PACs supporting them, so the thinking is that Cruz has so many super PACs supporting him because there is disagreement among big donors about how money should be spent supporting Cruz. By having multiple super PACs, donors have more control over how their money supports the candidate. If that is the case, it is not unreasonable to expect that some of these super PACs plan to run negative attack campaigns. We’ll have to wait and see which (other than Stand ForTruth) plan to do that in the coming weeks, though, as many of them have not yet spent any substantial money.