See Who's Defecting From Their Party This Election

As both parties struggle with unity this election, more non-traditional endorsements seem to be coming every day.

Several prominent Republicans announced this week that they plan to vote for Hillary Clinton and at least one high-profile Democrat has backed Donald Trump. Crossing over isn't new — there have been Obama Republicans, Reagan Democrats and a number of other defectors across the years.

Here's a list of some notable Republicans and Democrats who have endorsed the other party's candidate this election and in the recent past.

The 2016 Election

Richard Hanna

The New York representative became the first Republican in Congress to cross party lines and formally back Hillary Clinton on Tuesday. In an op-ed Hanna wrote and published on syracuse.com, he said: "While I disagree with her on many issues, I will vote for Mrs. Clinton. I will be hopeful and resolute in my belief that being a good American who loves his country is far more important than parties or winning and losing."

Meg Whitman

The Hewlett-Packard CEO also endorsed Hillary Clinton this week in an interview with the New York Times. "I will vote for Hillary, I will talk to my Republican friends about helping her, and I will donate to her campaign and try to raise money for her," Whitman said.

In a statement expanding on what she told the Times, Whitman said, "To vote Republican out of party loyalty alone would be to endorse a candidacy that I believe has exploited anger, grievance, xenophobia and racial division."

Regarding Clinton, she said in the statement "It is clear to me that Secretary Clinton's temperament, global experience and commitment to America's bedrock national values make her the far better choice in 2016 for President of the United States."

Whitman said Clinton has reached out to her, a sign that the Democratic nominee may be targeting prominent Republicans who might not have decided where to put their loyalties this year. Whitman was a top fundraiser for Mitt Romney's 2012 presidential bid.

Henry Paulson, Jr.

Paulson, a Goldman Sachs executive and former U.S. treasury secretary under George W. Bush, wrote in a June op-ed for the Washington Post that a Trump presidency is "unthinkable." He added: "When it comes to the presidency, I will not vote for Donald Trump. I will not cast a write-in vote. I'll be voting for Hillary Clinton, with the hope that she can bring Americans together to do the things necessary to strengthen our economy, our environment and our place in the world. To my Republican friends: I know I'm not alone."

Richard Armitage

Armitage is another high-ranking official from the George W. Bush administration — he served as deputy secretary of state, and also as an assistant secretary of defense during the Reagan years. In a June interview with Politico, Armitage said, "If Donald Trump is the nominee, I would vote for Hillary Clinton ... He doesn't appear to be a Republican, he doesn't appear to want to learn about issues. So, I'm going to vote for Mrs. Clinton."

Brent Scowcroft

Scowcroft was the national security adviser for Presidents Gerald Ford and George H.W. Bush. He endorsed Hillary Clinton in a June statement. Scowcroft wrote that he believes "Hillary Clinton has the wisdom and experience to lead our country at this critical time." He also said Clinton's experience as First Lady, a senator and secretary of state give her "truly unique experience and perspective."

Doug Elmets

Doug Elmets was a spokesman during Reagan's presidency. Elmets spoke at the Democratic National Convention, saying it was a "shock" to be speaking at the DNC, given his Republican views. He called the GOP platform the "most alarming" he'd ever seen: "It's laced with anti-immigrant, anti-gay, anti-women positions that do not represent the views of most Americans. That is why this year, I will vote for a Democrat for the first time."

Jim Cicconi

Cicconi worked as deputy chief of staff to George H.W. Bush, as well as a special assistant to Reagan. Now, he is the senior executive vice president at AT&T. In a statement, Cicconi said "Hillary Clinton is experienced, qualified, and will make a fine President. The alternative, I fear, would set our Nation on a very dark path."

Maria Comella

The former spokeswoman for Chris Christie, Republican governor of New Jersey, told CNN this week that she plans on voting for Hillary Clinton. She said Republicans are "at a moment where silence isn't an option." Her former boss was one of the earliest 2016 primary candidates to get behind Trump. She said she's voting for Clinton because she doesn't "believe it's enough to say you aren't for Donald Trump."

General Michael Flynn

Flynn is a registered Democrat, but was an early backer of Donald Trump and has been a strong critic of President Obama, according to the Washington Post, who also reported that he was considered as a potential running mate for Trump. He used to be the director of the Defense Intelligence Agency, but in 2014, he was forced out of his position. Of Trump, Flynn told Al Jazeera, "I don't agree with everything that he said ... but he's an individual who's willing to take on a challenge."

The 2008 and 2012 Elections

Colin Powell

In the 2008 and 2012 elections, former Secretary of State Colin Powell, a fixture in the George W. Bush administration, endorsed Barack Obama. In 2008, Powell told Meet The Press that Obama was reaching out in a "more diverse and inclusive way across our society." And in a 2012 CBS interview, Powell endorsed Obama again. He cited Mitt Romney's changing foreign policy positions as one reason he couldn't support him as the GOP nominee. He also praised how Obama handled the recession: "I saw over the next several years, stabilization come back in the financial community, housing is now starting to pick up after four years, it's starting to pick up. Consumer confidence is rising."

Charles Fried

Fried served as solicitor general during the Reagan administration and is a professor at Harvard Law School. He voted for Obama, citing John McCain's 2008 running mate, former Alaska Gov. Sarah Palin, as one of the main reasons why he could not support McCain's bid.

William Weld

In 2008, Weld, a former Republican governor of Massachusetts, endorsed Obama. He called the president a "once-in-a-lifetime candidate who will transform our politics and restore America's standing in the world," according to the Wall Street Journal. Weld is the vice presidential nominee for the Libertarian party in this year's election.

Lincoln Chafee

Chafee, former governor and senator of Rhode Island, launched a short-lived presidential bid during this year's Democratic primaries. But earlier in his career, he was a Republican. In an October CNN Democratic debate, Chafee said he switched allegiances (with a stint as an Independent in between) because "the party left me." In 2008, Chafee endorsed Obama while he was an independent. Chafee said he believed Obama was "the best candidate to restore American credibility, to restore our confidence to be moral and just, and to bring people together."

A. Linwood Holton, Jr.

The former Virginia governor crossed the aisle to endorse President Obama in 2008. Holton is also the father-in-law of Hillary Clinton's running mate Tim Kaine, who was one of Obama's earliest supporters. Holton campaigned for Obama in Virginia with his daughter, Kaine's wife Anne Holton.

Joe Lieberman

The former Connecticut senator endorsed John McCain in 2008. Lieberman had been registered as an independent since 2006, but as the New York Times reported, he caucused with Senate Democrats and was "in trade for the seniority privileges and committee chairmanships that accompany that party identification." Not too long before, in 2000, Lieberman was the vice presidential nominee, with running mate Al Gore. There were some reports that McCain wanted Lieberman as his running mate in 2008, but that a "fusion" ticket wasn't possible.

The 2004 Election

Zell Miller

The former Democratic senator from Georgia endorsed George W. Bush in 2004. He was a speaker at that year's Republican National Convention. In his speech, he criticized Democratic nominee John Kerry's voting record, saying that, with Kerry, voters will get a "get a 'yes-no-maybe' bowl of mush that can only encourage our enemies and confuse our friends." He also said George W. Bush was the one man he trusted with the country's future.

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