This "is a totally self-inflicted crisis," he noted. "There's nothing magic about March 1. There's no credit default or immediate impact or anything. It's a totally arbitrary date and it just makes no sense. ... We're in a very fragile recovery right now, and to suddenly slam the breaks on a significant hunk of federal spending could very easily tip us back into some kind of recession."

King supports gradual deficit reduction efforts, but warns that both parties' sacred cows have to be on the table. For Republicans, that means higher taxes. For Democrats, Medicare and Medicaid.

"The sequester hits the two areas of the budget (defense and non-defense discretionary spending) that are in pretty decent control," he insisted. "The conventional wisdom that the federal government is out of control and spending is out of control (in these areas) just isn't accurate in terms of the numbers."

Unlike a lot of congressional freshmen, King isn't a Washington novice. His first stint on Capitol Hill came in the 1970s as an aide to William Hathaway, then a Democratic senator from Maine. Asked what's changed the most since, King cited the sharp rise in partisanship as more conservatives became Republicans and more liberals became Democrats.

"When I was here in the '70s there was a swath of ideological views from the right to the left. But it wasn't necessarily strictly according to party," he said. "One of the most conservative people in the Congress was John Stennis of Mississippi. He was a Democrat. One of the most liberal people in the Congress was Jacob Javits of New York, a Republican. So there was a lot of overlap, and there was a lot more willingness to sit down and try to find bipartisan solutions."

King remembers sitting in closed committee sessions and seeing legislative giants "argue and disagree and say 'that won't work' or 'this won't work.' But ultimately they found some kind of consensus and moved on."

"I was here two and a half years and I don't remember a single filibuster on anything," he said.

Today, Maine still has ideological diversity across the political spectrum. King's home state colleague is moderate Republican Susan Collins, but that's the exception to the increasingly ironclad rule.

What happened to the liberal Republicans and conservative Democrats? Why did they disappear?

King cites three factors: Increasingly precise gerrymandering of congressional districts, the fragmentation and balkanization of the news media, and an explosion of special interest money due partly to court rulings like Citizens United.

"Both parties, but particularly the Republicans, have sort of pulled back toward their base," King noted. "The Republicans have practically no moderates left. And 25, 30 years ago the Senate was full of them. ... That's a recipe for confrontation. You add all those things together and it has created a much more partisan atmosphere."

Trailblazing Maine senator another hero

Next to the depiction of Chamberlain's Gettysburg heroics hanging in King's office, there is a black and white picture of Margaret Chase Smith.

Smith, a trailblazing Maine Republican who served in Senate from 1949 to 1973, was the first woman to have her name in placed in nomination for president at a major party's political convention. She also led the charge against fellow Republican Joe McCarthy with her "Declaration of Conscience" speech on the Senate floor in 1950.

"She was no liberal, but she was certainly an independent thinker," King said. "I think she would chafe at the expectation of partisanship. She was a bit of a maverick (and) was never one of the good old boys. ... She had no trouble standing on her hind legs and calling them as she saw them."

While King draws inspiration from the memory of Smith and other Maine political giants, he also turns to religion.

A lifelong Episcopalian, he attends church regularly.

"I believe in a God who is engaged with the world but that we are individuals of free will who carry out his will," King said. "It's a paradox."

Faith is "a source of strength and perseverance under difficult circumstances," he added. "I want to live my faith and reflect it in my work, but I view it as personal guidance for me, not how other people should act."

But it's the story of Chamberlain that may resonate most deeply in terms of King's independent political career. A four-term governor, president of Bowdoin College, and eventual Medal of Honor winner, Chamberlain fell out of favor with Maine's political establishment.

King notes that local Republicans turned on Chamberlain with a vengeance for failing to support the impeachment of President Andrew Johnson -- a stance which probably cost the Civil War hero a U.S. Senate seat.

"He was deemed too independent," King said. Chamberlain instead ended his career as surveyor of the port of Portland.

The lesson of Chamberlain's life? That's an easy one.

"Do the right thing," King said. "And don't be afraid to charge every now and then."