Mike Johnston became the first prominent candidate to join the 2018 governor’s race in Colorado, launching his Democratic campaign Tuesday with a promise to provide two years of debt-free college or job training to residents who serve the state.

“The magnitude of the challenges in this moment in our history require big, bold ideas and the proven track record to bridge divides and get results,” he said at a rally in Northeast Denver.

The 42-year-old former state senator’s debut is the start of what is expected to be a competitive contest for the party’s nomination. Former Interior Secretary Ken Salazar and U.S. Rep. Ed Perlmutter are considering making a bid — two big names that will draw significant money and attention.

Johnston’s campaign slogan is “Frontier Fairness” and he positioned his campaign toward the left end of the Democratic spectrum as he seeks to reach out to a party that remains divided by the feud between loyalists to Hillary Clinton and Bernie Sanders.

A 2008 campaign adviser to President Barack Obama on education issues, Johnston backed Clinton in the 2016 Democratic primary for president, even though Sanders easily won the Colorado caucus.

Johnston emphasized that his campaign will attract Sanders supporters — specifically his focus on college affordability, protecting immigrants living in the country illegally and his record against accepting campaign contributions from political action committees.

“I think the Bernie folks will find a lot of the values that they share will be evidenced in our campaign,” Johnston said in an interview.

The move will draw young supporters Johnston needs to build a campaign but it will open him to political attacks from Republican critics. Kelly Maher, a GOP operative, remarked that Johnston is “clearly making an appeal to run on the far left of his party with Bernie Sanders-style promises” and suggested his platform amounts to a “government force to make Coloradans pay for more programs.”

Johnston, whose state Senate term expired at the end of 2016, is best known as an eloquent speaker who championed education reform efforts and sponsored a contentious measure approved in 2010 to tie teacher evaluation to students’ academic growth and weaken tenure protections.

The details of his promise to provide debt-free college and career training remains unclear. He declined to put a price tag on the plan or explain how to pay for it, maintaining that it would be near revenue-neutral.

“All details we’ll focus on in the time ahead,” he said. “But the fundamental promise is opportunity for training in exchange for service to the state. And we believe that service to the state helps cover the cost for the training.”

Johnston hired Craig Hughes to advise his campaign. Hughes is one of the state’s top Democratic strategists and guided Obama and Sen. Michael Bennet to repeat election victories in Colorado.

With the race still taking shape, Johnston shrugged off the possibility that bigger Democratic names could trump his bid for the state’s top job.

“I know there are some really great folks who are thinking about it,” he said. “The question is do you have a vision for where you want to lead the state, and if so, you should show that vision to people and see if they believe it.”