The race in Texas is tightening. A new Quinnipiac University poll shows incumbent Republican Sen. Ted Cruz maintains a 5-point edge over Rep. Beto O’Rourke.

The race has become unusually close for a Republican stronghold as Election Day approaches. A Quinnipiac poll earlier this month showed O’Rourke stalled at 9 points behind Cruz. 

“O’Rourke is within striking distance, but time is running out,” said Peter A. Brown, assistant director of the poll.

O’Rourke has attracted celebrity endorsements and achieved record-breaking fundraising totals in his bid to unseat the polarizing senator and 2016 presidential candidate. 

But Cruz maintains a slight advantage, in part due to a “gender gap,” Brown said: Male voters prefer Cruz over O’Rourke at a 56 percent to 39 percent margin, while female voters prefer O’Rourke over Cruz at just a 52 percent to 45 percent split.

Independent voters prefer the Democrat 56 percent to 40 percent. That may not be enough to propel O’Rourke to victory, though, because there are few independent voters left to win over. Just 3 percent of likely voters told pollsters they didn’t know who they were leaning toward, and just 2 percent who have decided on a candidate said they might change their mind before heading to the ballot box. 

President Donald Trump was in Texas to rally support for Cruz last week, and the start of the polling period. 

Pollsters called 1,078 self-identified likely voters from Oct.22 through Oct. 28. Quinnipiac reported a 3.5 point margin of error.