Prop. 6 authorizes the state to take $2 billion from the Rainy Day Fund and use it for water conservation and infrastructure projects in Texas.
Joshua Blank is the chief research assistant on the Texas Lyceum Poll, which was conducted at UT Austin.
The independent non-partisan poll shows 44 percent of registered voters support Prop. 6.
But Blank says support goes up even more when you weed out voters who probably won't vote.
"And as we know in these constitutional elections, the turnout is abysmal. I mean even more so than for elections in general in Texas. And so when you sort of tighten the screen and look at just likely voters, who we defined as those who are extremely interested in politics, that actually the numbers change to be 49 percent in favor and only 36 percent opposed."
The poll shows 15 percent are undecided or refused to answer.
The survey of 1,000 registered voters in Texas also found that those polled think education is the most important issue facing the state, while the biggest issue nationally is the economy.
Texans also listed texting while driving as the biggest threat to safety on the roads.
The Texas Lyceum conducts the statewide poll of voters annually and will release more results later this week, including how voters are leaning in the 2014 governor's race and their job performance ratings for the Texas Legislature.
For more information, visit the KUHF Election Coverage page.