Whatever ups and downs Ethan Orr expected from his first session in the state House of Representatives, they did not include seeing T-shirts declaring him a traitor who stabbed conservatives in the back.

But after a tumultuous freshman session, that's the way it has turned out.

Orr, 39, won election to the House in November, a Republican in a Democratic-leaning district that includes the Catalina Foothills, part of midtown and part of the northwest side.

Orr sided with Gov. Jan Brewer's plan to expand Medicaid coverage to those who are within 138 percent of the federal poverty level and to return Medicaid coverage to childless adults fitting the income criteria. The proposal split the Republican Party.

Orr joined eight House Republicans and all the Democrats to vote in favor of the plan, and that's what has made him a traitor to some conservative Republicans, as well as a target for primary-election challenges next year.

Donna Alu, chair of the GOP in Orr's Legislative District 9, said she felt betrayed by his decision to side with the governor, who needed an end-of-session power play to win.

"I stood up for him for a really long time," Alu told me Tuesday. "I'm very disappointed because I thought he was an honest, upright person."

The outrage on the right is so hot these days that even Orr, whose most crooked feature is his goofy diagonal smile, can be labeled a liar.

Jan. 14, 2013, is the day that ended up defining Orr's freshman session - and perhaps his career. That's when he and the rest of Arizona learned of Brewer's plan to expand Medicaid coverage to take advantage of parts of the Affordable Care Act, or Obamacare, under which states are paid for giving more poor people Medicaid care.

Orr works as executive director of Linkages, a local agency that helps disabled people get jobs. He already favored giving coverage back to those who had lost it during the state's recent fiscal crisis.

Brewer's proposal was broader than he wanted, Orr said, but he chose to support it and try for some changes that would please both him and Republicans.

"My argument isn't to destroy the system. It's to reform the system so it works better," Orr said.

While Medicaid colored much of the session, the whole experience was powerful and at times dramatic for Orr.

He rented a two-bedroom condo with fellow GOP freshman Rep. Sonny Borrelli of Lake Havasu City. At first, the two would come back late from legislative sessions only to talk politics past midnight. But they soon learned they couldn't keep that up.

"I really enjoyed it. There were days I worked 18 hours. I would wake up, go to the gym, go to work, get home at 11 p.m, do some email and go to sleep," he said. "You were working these insane hours and you loved it."

Orr's district leans to the left, with about 37 percent of the registered voters Democrats, 33 percent Republicans and 30 percent independents.

His seatmate, Democratic Rep. Victoria Steele, said she was impressed with Orr's poise under pressure.

"It was very hard, and he struggled, but he never wavered," Steele said.

In fact, about a week before Brewer called a special session to push the Medicaid bill and her budget through, Orr went to discuss the Medicaid issue with some Goldwater Institute affiliates who opposed the bill, Orr said. Jim Click, who is Orr's political supporter and practically his employer - since Click founded and heavily funds Linkages - arranged the meeting, Orr said.

He still rejected their arguments.

That brought the drama of June 11, when Brewer called the special session, against the will of the Republican leaders of the House and Senate. Orr was key to making her plan succeed.

"The night we passed the budget was horrible. It was like the worst day of my life," Orr said. "But the last day was the way it was supposed to be. Everyone was just so tired from that fight, they just wanted to do it right."

Now Orr faces the music.

Tucsonan Roger Score, who made the "stabbed in the back" T-shirts naming each of the Republicans who sided with Brewer, hopes to help make Orr pay for what Score considers a betrayal. Score is one of Orr's constituents in LD 9 and said he had been assured the freshman would stick with the party line.

"He lied and said he was going to stand up for the Republican platform," he said.

Christine Bauserman, who helped found the United Republican Alliance of Principled Conservatives, said Orr could have been forgiven the Medicaid vote if he had not also gone along with the governor's budget. Now the alliance, also led by former Sen. Frank Antenori, is collecting signatures to put a repeal of the Medicaid bill on the ballot. And they're looking for candidates to challenge the "traitors" like Orr.

But even Alu, the legislative chair in Orr's district, isn't sure any Republican more conservative than Orr can win there. And the Democrats are quite willing to adopt him as their own: Steele acknowledged she's tried to persuade Orr to switch parties.

"He is amazingly courageous," Steele said. "He knows that this could cost him the election, but he did what was the right thing to do."

So while conservative Republicans are angry now, they ought to be careful what they wish for in the primary election. They just might get it in the general.

Contact columnist Tim Steller at tsteller@azstarnet.com or 807-8427. On Twitter: @senyorreporter.