WASHINGTON (Reuters) - Former Colorado Governor John Hickenlooper joined the growing field of Democratic presidential candidates on Monday, hoping to position himself as a centrist and an experienced officeholder who is best poised to defeat Republican President Donald Trump in 2020.

Hickenlooper, 67, will tout his business background and two terms in office, during which Colorado’s economy soared and the state expanded healthcare and passed a gun control law.

“I’ve proven again and again I can bring people together to produce the progressive change Washington has failed to deliver,” he said in a statement announcing his campaign on Monday, adding “we ... need to get things done.”

He is the second governor to enter the Democratic race, following Washington Governor Jay Inslee, and joins a slew of sitting U.S. senators who have already begun campaigns.

The field of Democratic candidates has grown to more than a dozen, with additional contenders still expected to join the field.

Hickenlooper will hold a campaign launch in Denver on Thursday and then travel to Iowa, the state which holds the first nominating contest, for the weekend.

The former governor, who left office in January, refused to air negative ads during his two gubernatorial campaigns, a position his aides insist he will carry into his presidential bid.

“There’s no profit margin in making enemies,” Hickenlooper says frequently to describe his political philosophy.

But staying positive will be harder to do in a presidential campaign expected to draw a large slate of Democratic hopefuls and against Trump, the presumptive Republican nominee who won in 2016 after a race replete with personal attacks on his opponents.

Former Gov. John Hickenlooper (D-CO) speaks at the United States Conference of Mayors winter meeting in Washington, U.S., January 24, 2019. REUTERS/Yuri Gripas

In announcing his bid, Hickenlooper did poke fun at himself.

“As a skinny kid with Coke-bottle glasses and a funny last name, I’ve stood up to my fair share of bullies,” Hickenlooper said in a video launching his campaign. “Standing tall when it matters is really what drives me.”

Hickenlooper is jumping straight into a debate within the Democratic Party about the best path to beating Trump in 2020. He joins those in his party who believe an establishment figure who can appeal to centrist voters is the way to win back the White House. Others believe a fresh face, and particularly a diverse one, is needed to energize the party’s increasingly left-leaning base.

Hickenlooper has so far refused to take corporate money for the political action committee, named Giddy Up PAC, he formed to allow him to raise and spend federal funds helping other candidates - a position he is expected to continue in his presidential bid.

Over the past two years, he has actively sought to bolster his bipartisan credentials.

In 2017, he asked then-Ohio Governor John Kasich, a Republican, to join him in advocating for compromise over the future of the Affordable Care Act, popularly known as Obamacare. The two held a series of national events touting the ability to reach bipartisan agreement.

The tour generated speculation that Kasich and Hickenlooper could mount a third-party bid for president and vice president together, rumors both camps denied.

Hickenlooper often speaks of his personal biography. After getting laid off from work as a geologist in the 1980s, he opened a brewery and pub. He frequently talks about the risk of opening his own business - a point he makes to argue he understands the needs of the economy.

He was elected mayor of Denver in 2007 and governor of Colorado in 2010.

In 2012, the state’s residents voted to legalize marijuana. At the time, Hickenlooper called legalization a bad idea but agreed to implement the will of the voters. He has since said he believes legalization and the oversight system created in the state worked.