Perhaps he thinks he has a shot at the nomination at a contested convention? Saw a Cruz interview yesterday and he (in my view) admitted Rubio was on his VP short list.
Exclusive: Marco Rubio rejected 'unity ticket' with Ted CruzUtah Sen. Mike Lee sought to arrange a shotgun wedding of his two Senate colleagues, but Rubio wasn't interested.
By ALEX ISENSTADT
03/21/16
Ted Cruz’s campaign has been exploring the possibility of forming a unity ticket with ex-rival Marco Rubio — going so far as to conduct polling looking into how the two would perform in upcoming primary states.
The motivation, hashed out in conversations among Cruz’s top aides and donors: to find a way to halt Donald Trump’s march to the Republican nomination.
It’s unclear whether Cruz’s campaign brass views a partnership with Rubio as realistic or quixotic. In Rubio’s orbit, according to three sources, it’s seen as an outright nonstarter — with Rubio telling his team he isn’t interested.
Yet in recent weeks, within Cruz’s camp, talk of a joint ticket has run rampant. Utah Republican Mike Lee, one of two senators to endorse Cruz, has emerged as an outspoken supporter of a unity ticket — and as a potential broker. The freshman, according to several sources briefed on the talks, has reached out repeatedly to Rubio to gauge his interest, but has been rebuffed.
Shortly before Lee endorsed Cruz on March 10, Lee and his advisers discussed the possibility of organizing a meeting between the Utah senator and Rubio in Florida, just days before the state’s primary, according to two sources. The meeting, though, never happened.
A Lee spokesman, Conn Carroll, declined to comment for this story. So, too, did spokespersons for Cruz and Rubio.
But the Cruz camp’s apparent fascination with the idea of joining forces with Rubio didn’t end with Lee’s efforts.
In recent days, Cruz’s team has begun to investigate how the two would fare on a prospective ticket. Over the past week, according to a person familiar with the Cruz team's internal deliberations, the campaign has conducted polling in forthcoming contests — including the one on Tuesday in Utah — in which questions are posed about the two running side-by-side.
The deliberations come at a time of rising anxiety among Republican leaders and donors about Trump, who many fear is becoming unstoppable. The real estate mogul holds a 256-delegate lead and is seen as the favorite in a number of upcoming primary states, including New York, New Jersey, and Pennsylvania — contests that could push Trump toward the 1,237 delegate number he needs to secure the Republican nomination.
At the very least, Cruz’s team is hoping for a Rubio endorsement. The two have been in touch since Rubio dropped out last week, and those close to he Florida senator say he’s open to endorsing his Texas colleague — especially if he believes there’s a pathway for Cruz to defeat Trump.
Yet some have pushed for more. Among the Cruz supporters who have been vocal about forging an alliance has been Doug Deason, son of billionaire megadonor Darwin Deason, who has deep connections in the Charles and David Koch fundraising network.
On March 2, the day after Super Tuesday, the younger Deason reached out to Cruz campaign manager Jeff Roe. Rubio had suffered a rash of defeats the night before, and Deason told Roe that it would make sense to reach out to the Florida senator’s team. By that time, Deason had been talking to a number of major Rubio donors, but now wanted to go to the official campaign to pitch the unity-ticket idea.
In an interview, Deason recalled telling Roe he wanted to call Marc Short, a senior Rubio adviser and former operative for the Koch-founded Freedom Partners political operation. After Roe didn’t object, Deason connected with Short and gave him his pitch.
Short’s response, Deason said, was unequivocal: Rubio wasn’t interested. (Short didn’t respond to a request for comment.)
“Rubio was too pompous to act on it. He believed his own internal polls and there was no swaying him away from staying in the race through the Florida primary,” Deason said. “If he had signed on before the first Super Tuesday, Cruz would have won all of the Texas votes and a lot more delegates. They may have very well won Florida.”
Appearing on Fox News after this story was published on Monday evening, Cruz was pressed on his campaign’s decision to look into a unity ticket and to poll its prospects. He said that he and Rubio haven’t spoken about it, nor had their respective staffs.
Cruz declined, however, to rule out a unity ticket.
“I think any Republican would naturally have Marco on their short list and you would look seriously to him as a vice presidential choice,” he said.
Erick Erickson, a vocal Trump critic who has floated the idea of a Cruz-Rubio alliance and last week organized a call by prominent conservative activists for a Republican “unity ticket,” said he thought it would be “very effective in stopping Trump.”
“I wish they would do it because it would provide counterprogramming to the Donald Trump show,” he said in an interview.
But Rubio’s camp is uniformly dismissive of the idea. “Different combinations have been floating out there for a little while — who could partner up with whom," said Utah Rep. Jason Chaffetz, a Rubio endorser. "But I didn’t take it too seriously.”
http://www.politico.com/story/2016/03/exclusive-marco-rubio-rejected-unity-ticket-with-ted-cruz-221066#ixzz43eZNWnMO 
