How the Ted Cruz, Rand Paul Friendship Is Turning Nasty

— -- It was May 2012 and Sen. Rand Paul took the stage at a tea party rally in Texas, telling the crowd he wanted to introduce them to a "gentleman" and a "friend" who he joked might be "too smart to be in the U.S. Senate," but who would take seriously the oath to defend the Constitution. Back then, Paul offered a gushing endorsement of a Texan named Ted Cruz who was in the midst of tough Senate race.

"I want to introduce at this point in time hopefully the next senator from Texas," Paul told the audience. Cruz shook Paul's hand, declaring "God Bless Rand Paul."

It would be one of many times the two men would support each other over the last three and a half years.

But now, in the throes of a presidential campaign that is pitting Cruz and Paul against one another in a crowded field of GOP candidates, their once-supportive relationship appears to be turning into a fierce rivalry. Just this week, the Cruz campaign released a video featuring several libertarian-minded supporters of Paul’s father and former presidential candidate, Ron Paul, who are now backing Cruz. Meanwhile, Paul has publicly criticized Cruz on talk radio.

"They’re in a situation where they’re competing against each other for voters in a way that Jeb isn’t competing against Rand for the same votes," said Doug Heye, a longtime Republican strategist and former communications director for the Republican National Committee. “When presidential politics enter the equation, a lot of things get thrown out of the window and that’s what we’re seeing now.”

The video released by the Cruz campaign touting the endorsements of one-time Ron Paul supporters, including one Iowa Republican who had been endorsed by Rand Paul, was the opening salvo in the simmering fight between the two men who have the same day job on Capitol Hill.

The video shows interviews with the former Ron Paul supporters as they describe libertarian principles and their love of Ron Paul. They then turn to say why Cruz is the best candidate to carry on Ron Paul's work. One supporter says that Ron and Rand Paul's previous endorsement of Cruz in 2012 drew them to Cruz.

"There are a lot of things that impress me about Ted Cruz and the way that he’s really picked up the mantle of Ron Paul in a lot of ways," says one supporter in the video.

Another says, "I see the same courage of conviction in him that I see in Ron Paul."

For Ron Paul's son, who is also fighting to make it to the White House, it's hard to imagine that those words don't sting.

The Cruz campaign also formed a coalition called "Liberty Leaders for Cruz," an effort to appeal to libertarian voters -- a clear attempt to poach directly from Rand Paul's base.

"No one represents the values of liberty better then Senator Rand Paul,” Paul campaign spokesman Sergio Gor said in a statement responding to the moves without mentioning Cruz by name. “While others tout a handful of supporters, the vast majority remain committed to Senator Paul and his fight to restore liberty in 2016."

The recent sparring between the two senators’ campaigns belies a much more collaborative history in U.S. Senate.

When, in 2013, Paul filibustered for nearly 13 hours against President Obama's nominee to lead the CIA, Cruz helped the Kentucky senator catch his breath by reading supportive tweets. And six months later in September 2013, when Cruz filibustered against Obamacare for 21 hours, he'd reportedly sought advice from Paul beforehand. Even this year, after both had announced their White House bids, Cruz helped Paul during his more than 10-hour filibuster against the National Security Agency surveillance program. Cruz thanked Paul for his defense of liberty and acknowledged that they didn't completely agree on the issue.

But this week, after they struck different tones in floor speeches, Paul lashed out at Cruz. During his hour-long speech, he repeatedly bashed Senate leadership, including Senate Majority Leader Mitch McConnell. Cruz accused Speaker of the House John Boehner of cutting side deals with Democrats and said that both McConnell and Boehner had done more to help Democrats than Republicans. Cruz said they "surrender" to President Obama and his priorities. Earlier this summer, Cruz accused McConnell of lying about a vote on the Export-Import Bank.

“Ted has chosen to make this really personal and chosen to call people dishonest in leadership and call them names, which really goes against the decorum and also against the rules of the Senate, and as a consequence he can’t get anything done legislatively. He is pretty much done for and stifled and it’s really because of personal relationships, or lack of personal relationships, and it is a problem,” Paul told Fox News Radio on Tuesday. “I approach things a little different. I am still just as hardcore in saying what we are doing. I just chose not to call people liars on the Senate floor and it’s just a matter of different perspectives on how best to get to the end result.”

In an interview on the Hugh Hewitt radio program on Wednesday, Cruz responded to Paul's comments that he is engaging in personal attacks.

“The attacks he directed at me are not terribly surprising particularly given that Rand campaigned for Mitch McConnell and then Mitch McConnell in turn has endorsed Rand for president,” the Texas senator said. “But I have no intention of responding in kind to Rand’s attacks.”

In the same breath, Cruz referred to Paul as a “friend of mine” and a “good man.”

He went on to say, "None of this is personal. The media loves to characterize it as a battle of personalities, as a soap opera. Look, I think most Americans could care less about a bunch of politicians in Washington bickering like schoolchildren. It doesn’t matter and so if others attack me, I don’t reciprocate. I will not throw rocks."

And while Cruz may not be throwing the rocks himself, his campaign continues to highlight the Ron Paul supporters who are endorsing him. They issued a second release this week naming more Ron Paul supporters who are standing behind Cruz. Today, Paul's campaign announced state caucus leaders endorsing the Kentucky senator and on the list was a member of Cruz's Nevada leadership team.

Though Paul’s comments to Fox New Radio this week were his most blunt to date about his rival, a super PAC supporting the Kentucky senator, America’s Liberty PAC, released a video earlier this year questioning Cruz’s American citizenship and referring to him the "Capitulating Canadian." (Cruz was born in Canada to an American mother).

The two men continue to fight for traction in this year's crowded GOP field, but Cruz seems to be faring better in the polls. ABC News’ latest analysis of recent national polls according to the third presidential debate criteria shows Cruz hovering in sixth place with Paul nearly missing the cut in 10th place.

Heye acknowledged that Cruz's move to appeal to supporters of Paul might pay dividends.

"It’s clear that Paul’s campaign now faces an existential crisis,” Heye said. “Here are a portion of voters that can possibly be picked off and by going after them, you are potentially hastening that fall.”