Republican Senator Ted Cruz may be at risk of losing his seat in Texas, an internal polling memo from a GOP super PAC aiming to flip the Senate has suggested.

The memo from the Senate Leadership Fund (SLF), which was obtained by Politico, points to problems for Cruz as polling shows his Democratic challenger, Representative Colin Allred, closing the gap between them with less than a month before Election Day.

The PAC’s October polling had Cruz just 1 point ahead of Allred, when he had been leading by 3 points in September.

Democrats are pouring money into the Senate races in both Texas and Florida, which are viewed as the party’s best chances to flip seats in November and retain its thin Senate majority amid concerns about retaining Senator Jon Tester’s seat in Montana.

“We still have a lot of work to do to maximize our gains in this critical Senate election,” SLF president Steven Law wrote in the memo. “We need to add media markets and expand into the final week in all our target states. We also have to guard our flanks.”

The memo notes that Allred “has been heavily outspending” Cruz on television, while GOP outside groups “joined the fray in late September and narrowed Allred’s spending advantage.”

It also pointed to the candidates respective favorability ratings, with Cruz at 49 percent viewing him in a favorable light, against 48 who feel the opposite. Allred’s favorability rating, however, stands at 48 percent positive to 36.

Newsweek has contacted the Cruz and Allred campaigns for comment via email. The Senate Leadership Fund has been contacted for comment via email.

Other polls have shown the race between Cruz and Allred tightening, with the Republican saying earlier this month that Democrats “are coming after me with everything they have.”

Last month, the Democratic Senatorial Campaign Committee announced a “multimillion dollar investment” in television advertising in Texas and Florida.

“We can also go on the offense. What we’re seeing in both Florida and in Texas is very exciting,” Senator Gary Peters, the chair of the Democratic Senatorial Campaign Committee, said on MSNBC’s PoliticsNation earlier this month.

“We’re seeing momentum (…) I’m confident we can hold the Senate, and we really have great pickup opportunities as well.”

“Texas voters have had reservations about Ted Cruz for years,” Costas Panagopoulos, a political science professor at Northeastern University, told Newsweek. “He only squeaked by narrowly to win re-election in 2018. The poll results spell real trouble for Cruz in the current cycle. The estimates suggest the race is tied or even that Allred may be ahead.”

Meanwhile, Thomas Gift, an associate professor of political science and director of the Centre on U.S. Politics at University College London, told Newsweek: “There’s a saying that Texas is where Democratic money goes to die. While there’s a chance that Cruz could lose his seat, the Lone Star state almost always turns out to be redder than many polls—and experts—suggest.”

He added: “While demographic change in Texas is certainly trending toward Democrats, we’re not yet at the point where Republicans have lost their advantage. Toppling Cruz would be a high-profile win for Colin Allred, but by dint of the fact that he has a D next to his name, his work will be cut out for him.”

However, Dafydd Townley, an expert on American politics who teaches at the University of Portsmouth in the United Kingdom, previously told Newsweek that Democrats have a plausible chance of securing their first Senate seat in Texas since 1988.

“The Cruz/Allred race for the Senate has given Democrats hope that they can achieve victory in a state that has been dominated by the Republican Party in recent history,” Townley said. “For decades, the hope that Texas could be a ‘purple’ state, and therefore key to both congressional majorities and the presidential election, has dissipated with continued Republican victories. However, the margin of those victories has been diminishing and this Senate race really does seem to be a genuine contest.”

Update 10/14/24, 11:10 a.m. ET: This article has been updated with comment from Thomas Gift and Costas Panagopoulos.