*Editor's note: This story has been updated to include final passage of the bill.

The Texas Senate gave initial approval Wednesday to legislation that would eliminate straight-ticket voting in all elections.

By a vote of 20-10, senators passed House Bill 25 over objections from Democrats who warned of unintended consequences — including a disproportionate impact on minority voters. (Update, May 18: The Senate gave the bill final approval on a 19-11 vote.)

"Frankly, I don’t see any purpose for this legislation other than trying to dilute the vote of Democrats and, more specifically, minorities," said state Sen. Royce West, D-Dallas.

The bill's supporters say it would force voters to make more informed decisions in individual elections. "What we're doing is showing every race matters," the Senate sponsor, Republican state Sen. Kelly Hancock of North Richland Hills, said Wednesday.

The legislation's backers also argue it would bring Texas in line with at least 40 other states that do not allow straight-ticket voting, the option for voters to automatically cast their ballot for every candidate from a single party. Straight-ticket ballots made up nearly 64 percent of total votes cast in the state's 10 largest counties in 2016.

The preliminary approval of HB 25 on Wednesday came after Hancock amended it to postpone its effective date from September 2017 to September 2020. That will allow candidates more time to prepare for the change, Hancock said.

The vote also followed a nearly hourlong debate between Hancock and Democrats who sought to show he had not done due diligence in assessing whether the bill would disproportionately affect minority voters. A federal judge found as much when it blocked a similar law last year in Michigan.

Hancock repeatedly downplayed the implication of that ruling for House Bill 25, saying it would travel a different route through the courts if it becomes law and faces a legal challenge. He also dodged questions about whether he had especially taken into account perspectives on the proposal from groups concerned with minority voting rights, repeatedly emphasizing there was a committee hearing where they could have testified.

"We considered all voters," Hancock said as West grilled him over the bill's potential to disproportionately impact minority voters. "We considered each and every voter."

A final Senate vote on HB 25 is expected Thursday. It would then head back to the lower chamber, where members would decide whether to approve the Senate’s changes before sending it to the governor for his signature.

While the bill got a boost from House Speaker Joe Straus, R-San Antonio, this session — and Lt. Gov. Dan Patrick has previously supported ending straight-ticket voting in judicial races — Gov. Greg Abbott has been less vocal. His office did not immediately respond to a request for comment.

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