Ban capital punishment, halt drone strikes and bring home Edward Snowden. These are a few of the radical proposals unveiled by Lincoln Chafee in his low-key, no-frills presidential campaign announcement Wednesday evening. Standing before a bland white wall in front of a sparse audience at a George Mason University venue in Arlington, Virginia, Chafee – the former Republican U.S. senator turned independent Rhode Island governor – became the fourth official Democratic candidate for the White House in 2016. Chafee delivered on his promise of bold, different ideas, which explains why he may be the biggest long shot in this cycle's sprawling field of candidates. His most unique proposition: Transferring the United States to the metric system.

"Here's a bold embrace of internationalism: Let's join the rest of the world and go metric. Only Myanmar, Liberia and the United States aren't metric and it will help our economy," Chafee said. "It doesn't take long before 34 degrees is hot."

The bulk of Chafee's launch speech focused on foreign policy. One of his chits with progressive voters is that he was just one of 23 senators – and the only Republican – to vote against the war in Iraq.

"We need to be very smart in these volatile times overseas," he said. "We have to change our thinking. We have to have a way to wage peace."

A Chafee administration would ban political donors from being ambassadors, swear off the torturing of foreign prisoners and stop the drone strikes that have been used more frequently by the U.S. military in recent years.

On allowing Snowden to come back to the U.S., Chaffee did not elaborate on what consequences, if any, the former National Security Agency employee, who leaked surveillance program secrets to the press, should face.

The organizational challenges of Chafee's unlikely upstart bid already were on display last week when his wife was spotted attempting to reach out to staffers about his Facebook password.

But even if he ultimately bows out with a whimper, he will at least have made a small imprint on history.

He's the first major-party candidate from Rhode Island to run for the presidency since it became a state 225 years ago.

