JEFFERSON CITY, Mo. – 15 Republicans joined a united Democratic caucus on Wednesday voting against an override of the controversial income tax cut bill, House Bill 253.

“Ultimately, this was a political battle, in which our state lost,” House Speaker Pro Tem Denny Hoskins said in a statement Wednesday afternoon soon after the vote.

While the lead-up to the vote is over, the real political battle may have just begun. A total of 15 Republicans broke ranks with their party on Wednesday to oppose the bill, including Sue Entlicher, Travis Fitzwater, Dennis Fowler, Lyndall Fraker, Elaine Gannon, Kent Hampton, Jeff Messenger, Donna Pfautsch, Craig Redmon, Lyle Rowland, Mike Thompson, Nate Walker, and David Wood.

Throughout the summer-long campaign, the bill’s supporters — a coalition of business and conservative groups working together through “Grow Missouri” — threatened to back primary challenges to Republicans who voted against the tax cut.

Club for Growth, an organization backed by St. Louis billionaire Rex Sinquefield (who funded much of the pro-HB 253 effort this summer), posted a photo on Twitter of the vote count with the comment, “Making my list, checking it twice.”

Carl Beardon, executive director of United for Missouri, said while his organization does not endorse candidates, they will be engaging in a “education” effort in districts where Republicans opposed the tax cut bill.

“We will educate voters in the GOP dissenting districts and at least two Senate districts that the person seeking their votes either don’t read bills before they vote or they don’t understand them and still vote YES,” he wrote in an email.