It wasn’t all that long ago, The Hill reminds readers, that Ted Cruz went out of his way to alienate his colleagues in the Senate Republican caucus. Now, however, they’re riding to his rescue — out of necessity, if not out of affection. Fundraising groups tied to Senate GOP leadership have given Cruz a cash infusion as polls tighten between the Texas incumbent and his Democratic challenger Beto O’Rourke:

GOP leaders and rank-and-file Republicans alike are putting aside those differences in the face of an existential threat to Cruz’s Senate career in the form of O’Rourke, the skateboarding ex-punk rocker who has amassed a stunning $23.6 million war chest. The latest fundraising reports show O’Rourke with more cash on hand, $13.9 million, than Cruz, at $9.3 million. …

A Cruz loss would also put GOP control of the Senate very much at risk, which has senators who have sometimes been at odds with the tough-talking Texan coming to his aid.

The entire Senate Republican leadership hosted a fundraiser for Cruz at the end of June and Senate Majority Leader Mitch McConnell (R-Ky.), whom Cruz once famously called a liar on the Senate floor, has made the maximum donation to Cruz’s campaign through his leadership PAC, Bluegrass Committee.

Cruz has also received $5,000 from Senate GOP Whip John Cornyn’s (R-Texas) leadership PAC, $10,000 from Republican Policy Committee Chairman John Barrasso (R-Wyo.), and $10,000 from Sen. Roy Blunt’s (R-Mo.) Rely on Your Beliefs Fund.

The rally call has gone beyond the Senate, going to the other end of Pennsylvania Avenue and as far south as Austin. Donald Trump’s announcement last month of an October rally to show support for Cruz came after urging by Texas lieutenant governor Dan Patrick lobbied the White House for an intervention. Politico reports that the party has sounded an all-hands-on-deck alert to raise funds for a seat that should have been an easy hold.

But it’s not just to save Cruz’ seat, either:

Patrick, who chaired Trump’s 2016 campaign in the state, made the case that a Trump visit was needed to boost turnout for Cruz and the rest of the Texas Republican ticket. The lieutenant governor soon got his wish: Trump announced on Twitter late last month that he was planning a blowout October rally for Cruz, his former GOP rival.

The previously unreported meeting comes as senior Republicans grow increasingly concerned about the senator’s prospects in the reliably red state, with some expressing fear that an underperformance could threaten GOP candidates running further down the ballot. Cruz’s Democratic opponent, Rep. Beto O’Rourke, has raised barrels of cash, closed the polling gap and emerged as a cause célèbre of liberals nationwide. …

With O’Rourke outraising Cruz more than 2 to 1 during the past quarter, right-leaning organizations have begun routing resources to the state. The anti-tax Club for Growth, which spent millions on Cruz during his 2012 Senate bid, has started a seven-figure advertising blitz aimed at tearing down the Democratic congressman. The organization has begun polling the race, and David McIntosh, the organization’s president, recently traveled to Texas to meet with donors who could help fund the barrage. More than $1 million has been raised so far, people close to the group say.

A handful of other well-funded groups are considering joining the effort, including the Koch-backed Americans for Prosperity, the Mitch McConnell-aligned Senate Leadership Fund, the newly formed Senate Reform Fund, and Ending Spending, which in the past has been bankrolled by major GOP financiers including New York City investor Paul Singer. Some of the groups have been in touch with one another as they weigh their next moves and try to determine how much their help is needed.

If O’Rourke uses all that cash to generate a better-than-usual turnout statewide, it might be enough to flip a few House seats to the Democrats. Republicans have to strengthen their GOTV infrastructure in Texas to counter O’Rourke, but that has a cost, as Politico’s Alex Isenstadt also points out. The money being raised by outside groups and Senate leadership PACs would normally have gone to contests in states that would normally be battlegrounds, or where Democratic incumbents are weak. Every dollar that Republicans and their allies shift to Texas is a dollar that won’t be spent in Indiana, West Virginia, Missouri, or Pennsylvania — where court-ordered redistricting has put several GOP seats in danger.

Just what kind of danger is Cruz in? Is it necessary to flood the zone like this? According to RealClearPolitics’ poll tracking, it’s not just the money imbalance that should worry the GOP. Cruz has a lead in the RCP average of just 4.4%, and his numbers are weak for an incumbent of the dominant party in the state. Only one poll put his support at 50% or higher in the last two months, and the most recent from Emerson only has him at 39% against O’Rourke’s 38%. Quinnipiac and Marist have Cruz at 49% in two polls from late August, but that’s still pretty weak in a state where Republicans dominate. Furthermore, O’Rourke’s numbers have been rising from the mid-30s in the spring, while Cruz’ haven’t changed much at all.

Cruz still is the favorite to win his seat in November. However, it’s no longer a slam dunk, and the big cash infusion tells us that Republicans know that too. As John Cornyn told donors, “We’re not bluffing.” Neither are O’Rourke and the Democrats.