Throwing cold water on Democratic hopes to gain influence in the Texas Senate, Lt. Gov. Dan Patrick vowed Thursday to change — again — a rule that requires a certain amount of cooperation before senators can vote on legislation.

Currently, 19 of 31 senators must support a bill before it can get a floor vote.

With Republicans clinging to 19 Senate seats — including one in a traditionally Democratic district that is up for election in November — Democrats hope that flipping at least one seat would bring greater clout when the Legislature next meets in 2021.

But Patrick, who presides over the Senate, said continued conservative Republican leadership on state policy and laws was too important to give Democrats any power to stand in the way.

"If we are still the majority, but the minority has the power to overrule us, we cannot let that stand," Patrick said during a lunchtime discussion at a policy orientation sponsored by the Texas Public Policy Foundation, a conservative Austin think tank.

If Democrats flip at least one Senate seat in November, Patrick vowed to lower the threshold on allowing floor votes — or eliminate it altogether.

"If we lose one or two seats," Patrick said, "we might have to go to a simple majority" to allow floor votes on bills.

When Patrick became lieutenant governor in 2015, legislation needed support from 21 senators to get a floor vote — a 64-year tradition that raised the ire of conservatives when it was used to block, for example, consideration of strict abortion regulations in the previous regular session.

One of Patrick’s first acts in office was to lower the 21-vote rule to the current 19 votes.

At the time, Democrats argued that the 21-vote rule required senators from both parties to work with colleagues to improve legislation and fostered the collegiality that is sorely missing in the U.S. Congress.

On Thursday, Democrats decried the prospect of seeing the supermajority requirement further watered down or eliminated.

"To threaten to change the rules as more Democrats get elected is yet another example of Republicans circumventing Texans and jamming through unpopular Republican legislation that harms Texas families," said Manny Garcia, executive director of the Texas Democratic Party.

Garcia suggested that Republicans, fearing defeat at the polls, "are rigging the rules in their favor."

"The Texas Capitol belongs to all the people of our great state. The rules of the Senate are there for a reason — to protect the interests of all Texans from right-wing extremist legislation and create a deliberative body," he said.

Sen. Carol Alvarado, D-Houston, said the proposed change would upend the Senate’s tradition of deliberation and comity.

"In Texas, we pride ourselves on not being like Washington, not being extremely divisive and partisan, and this statement just takes us there. You can't keep changing the rules to keep you in power," said Alvarado, who is head of the Senate Democratic Caucus but said she was speaking for herself because she had not yet spoken to other Democrats.

But Patrick, who was a senator for eight years before becoming lieutenant governor, said he could not let Democrats dictate Senate priorities.

"There are some members in the Senate who forget the days when we had to go to a Democrat to get permission to bring a bill to the floor," he said. "I remember; I was there. I don’t want to let that happen again."

Future election victories by Democrats and the left, he said, would threaten "the future of Texas and the economy" and endanger Texas’ ability to launch conservative policies that often fan out to other states.

"We are at a crucial point in our history where, if we would lose the election in November to the left, there are going to be a lot of people in Texas starting to think, you know, do we want to be a country again?" Patrick said.

In the 2020 election, Democrats are particularly targeting state Sen. Pete Flores, R-Pleasanton, whose special election victory in 2018 was aided by Democratic fractures in a district that Flores lost by 15 points when he also ran in 2016.

With nobody expecting Democrats to erase the GOP majority in the Senate, lowering the Republican majority to below the 19-vote threshold has been a crucial factor in drawing Democratic attention to the Flores race.