Biiiiig caveat upfront: This comes from Public Policy Polling, a left-wing outfit, and was paid for by a group called, ahem, End Citizens United. Feel free to discount accordingly. Before you do, though, note that (a) Quinnipiac, a respected pollster, had Cruz ahead by a similar six points a few days ago, and (b) the last poll of the race commissioned by End Citizens United apparently had him at 50 percent. It’s not like the group’s data has been remorselessly favorable to O’Rourke.

Either way, the fate of the Senate will not turn on this race. Cruz will very likely win, but there’s no plausible scenario in which he gets upset while the rest of the GOP performs respectably nationwide. If Texas goes blue, it’s a coast-to-coast bloodbath. The only suspense will be the Democrats’ margin in the Senate.

The survey, conducted by the left-leaning firm Public Policy Polling, found O’Rourke, an El Paso congressman, trailing Cruz 42 percent to 46 percent. That’s closer than the 8-point lead PPP gave Cruz when it surveyed the race in January for End Citizens United, a Democratic group focused on campaign finance reform…

Once voters were told about O’Rourke’s decision to reject PAC money, he took the lead, 46 percent to 43 percent. The January poll produced a similar result, giving O’Rourke a 2-point advantage after respondents were informed he isn’t taking PAC money.

The most recent poll is the third this week to show a single-digit race between Cruz and O’Rourke. Cruz’s campaign was critical of the two previous surveys, taking issue with their methodologies and samples.

Just a fluke? Not to the pros at Cook Political Report. They’re moving the race, which in most years would be “solid Republican,” from “likely Republican” to “lean Republican.” Next stop: Toss-up.

Of the eight general election polls aggregated on RealClearPolitics, six showed Cruz at between 47 percent and 51 percent. In those same six polls, O’Rourke was between 39 percent and 43 percent. While O’Rourke has room to grow, Cruz is consistently closer to and in some cases at or above 50 percent. In a state as Republican as Texas, those last few points that O’Rourke needs to hit 50 percent are going to be very hard (and very expensive) to get. There are some observers who believe that there simply aren’t enough Democratic and Democratic-leaning independents voters to push O’Rourke across the line. In fact, a Democrat hasn’t represented Texas in the Senate since 1993 when appointed U.S. Sen. Bob Krueger served for six months (Democrat Lloyd Bentsen served from 1971 – 1993). There are others who believe that O’Rourke can attract some more establishment Republicans who just don’t like Cruz. In a cycle like this, it is hard to simply dismiss such a proposition.

O’Rourke has outraised Cruz this year and has nearly $5 million more in the bank than Cruz does. Benjy Sarlin poses an intriguing question: Are Cruz’s numbers soft because of lingering hard feelings towards him by Trump fans in Texas? There’s some reason to believe that Cruz himself is worried about it. His tweets lately calling on Facebook to un-ban Alex Jones and for prosecutors to take a look at James Gunn for his old social media postings seem aimed squarely at right-wing populists, exactly the type of people most likely to hold a grudge against him for not endorsing Trump at the convention in 2016.

But the Quinnipiac data doesn’t back it up. Cruz’s job approval among Texas Republicans is 84/9. By comparison, Trump’s approval is 84/12. (John Cornyn’s is 59/9.) Gov. Greg Abbott is rated slightly more highly among Republicans than Cruz at 87/6, but the big difference between them is among independents. Cruz splits 47/47 among indies on job approval whereas Abbott splits 55/33. Cruz’s problem is the same as it’s always been — righties actually like him quite a bit, it’s, er, everyone else that’s the problem. Which, I suspect, is why he took the unusual step for an incumbent of challenging his opponent to five debates. He’s worried about those independents, most of whom are likely to be right-leaning, viewing the race as a pure “Cruz vs. Not Cruz” choice. If that happens, it’s not crazy to think “Not Cruz” pulls an upset. If, however, he lets those indies see for themselves that O’Rourke is a true-blue progressive, then it’s no longer “Cruz vs. Not Cruz.” It’s “Cruz vs. the Liberal.” In Texas, Cruz wins that race.

An interesting question looms for him: Does he want Trump campaigning for him or not? *If* Sarlin’s right that there’s some faction of populists in Texas who are iffy on Cruz, the only thing that might get them to the polls is an in-person seal of approval from the MAGA-in-chief. The risk is that having Trump show up in the state risks confounding the “Cruz vs. the Liberal” narrative that the campaign is setting up. Because Trump dominates media so totally, a presidential cameo could turn the race into a “Pro-Trump vs. Anti-Trump” narrative on Election Day, which is probably still a winner in Texas but not as sure a winner as “Republican vs. the Liberal” is. I think Cruz will politely ask him to keep his distance. A tweeted endorsement will suffice.

Exit question: President O’Rourke?