Sen. Ted Cruz (R) leads his Democratic challenger, Rep. Beto O'Rourke, by just 1 point in their Texas Senate race, well within the margin of error of a new poll from Emerson College.

The survey, which was released on Monday, found that Cruz leads O'Rourke 38 to 37 percent. Four percent of voters favor a different candidate and 21 percent remain undecided.

The survey comes as O'Rourke continues to gain momentum in his quest to unseat Cruz.

While Texas has not elected a Democrat to the Senate in three decades, polls continue to show that the race between O'Rourke and Cruz will be tight. Just last week, a new NBC News-Marist survey found that Cruz led O'Rourke by 4 points.

In addition, the Cook Political Report shifted the race from its "likely Republican" column to "lean Republican" earlier this month.

Emerson College notes that O'Rourke is a popular candidate, which could spell trouble for Cruz. According to the survey, the three-term congressman is viewed favorably by 37 percent of registered voters.

O'Rourke leads Cruz among voters in the 18-34 and 35-54 age ranges. On the other hand, Cruz has the advantage among voters between 55 and 74 and over the age of 75.

The Emerson College survey was conducted from Aug. 22 to 25 among a population of 550 voters. The margin of error is 4.4 percentage points.