INDIANAPOLIS | State Sen. Karen Tallian, D-Ogden Dunes, ended her campaign for Indiana governor Monday after the AFL-CIO, a coalition of Hoosier labor unions, endorsed John Gregg.

Tallian's decision makes Gregg, a former House speaker and former president of Vincennes University, the likely 2016 Democratic nominee for governor — setting up a probable rematch of the 2012 contest that saw Republican Gov. Mike Pence outpoll Gregg by 3 percent.

The veteran state senator said without volunteer and monetary support from organized labor, she had little chance of successfully competing against Gregg in the Democratic primary race. On Saturday, the United Steelworkers also endorsed Gregg for governor.

"I've got no choice," Tallian said. "I can't fight all of that."

Tallian supporters privately questioned why Indiana's labor unions would turn their backs on the lawmaker who has fought their battles in the Republican-controlled Senate for the past 10 years as the top Democrat on the Pensions and Labor Committee.

But that lack of labor support showed in Tallian's meager $23,751 fundraising total for the first half of the year, 88 percent of which came from Tallian's Senate campaign fund.

In contrast, Gregg raised $1.7 million during the same six-month period, including many large donations from state and national labor groups. Pence has $4.2 million in his campaign fund.

The third Democratic candidate for governor, State Superintendent for Public Instruction Glenda Ritz, also struggled to raise money and ended her campaign Aug. 7 in favor of running for a second term as Indiana's schools chief.

Tallian, whose Senate term does not expire until 2018, isn't thinking about immediately running for another state office. She said she's not discussed with Gregg the possibility of being his lieutenant governor.

She also refused to comment on speculation that she is being urged to run for attorney general, which is an open race now that Republican Greg Zoeller is not seeking a third term and running instead for a southern Indiana Congressional seat.

Tallian announced her campaign for governor May 10 — exclusively in The Times — promising to be the progressive voice in the Democratic race.

She said following Pence's "religious freedom" debacle that embarrassed Hoosiers by making the state appear eager to discriminate against gays and lesbians, Indiana needed a candidate that had a Grand Canyon's worth of separation from the Republican's policies.

"The differences between Mike Pence and I are wide and deep ... and people might just want to take a view from the other side now," Tallian said at the time.

Having campaigned across Indiana over the past four months, Tallian said she knows now more than ever that Hoosiers are ready for a change in the governor's office.

"People are very unhappy with the direction our state is going under Mike Pence," Tallian said, citing school funding and infrastructure as two key problem areas.

She is confident, based on the support her campaign garnered and her interactions with Hoosiers at county fairs and elsewhere, that a Democrat can be elected in what is traditionally considered a Republican-leaning "red state."

"It's still my belief that Indiana isn't as red as the gerrymandered Legislature would have you believe," Tallian said. "That's been confirmed in my opinion."

Gregg said Tallian remains both his friend and "a true champion for working Hoosiers."

"I look forward to standing with her in the years ahead to improve our schools, rebuild our infrastructure and create an economy that works for all workers," he said.