WASHINGTON – Former Secretary of State Hillary Clinton praised Sen. Mitt Romney for being the lone Republican to vote to remove President Donald Trump from office in the Senate impeachment trial and condemned his colleagues for voting "to betray" their oath to defend the Constitution.

"I wasn't surprised because it's hard to get 67 votes to convict and remove somebody," Clinton said of her 2016 opponent's acquittal during an interview on "The Ellen DeGeneres Show" that airs Thursday. "But I was still disappointed that not more of the Republicans were willing to take the stand that Mitt Romney took."

She said the senator from Utah delivered an "extraordinary speech on the floor of the Senate talking about why he felt the weight of history on his shoulders."

Trump faced articles of impeachment on abuse of power and obstruction of Congress stemming from allegations that he used military aid to pressure Ukraine into opening investigations for his own political benefit.

Citing his religious convictions and his oath to be an impartial juror, Romney voted to convict Trump on the abuse of power charge but voted not guilty on obstruction of Congress.

"With my vote, I will tell my children and their children that I did my duty to the best of my ability, believing that my country expected it of me," Romney said in his speech explaining his vote. "I will only be one name among many, no more or less, to future generations of Americans who look at the record of this trial. They will note merely that I was among the senators who determined that what the president did was wrong, grievously wrong."

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Clinton – whose husband, former President Bill Clinton, survived his own impeachment trial in 1999 – said Romney's vote was "really important" because "it was the first time in our history that there has ever been a bipartisan vote to convict."

Clinton noted that while Romney – who got more than 60 million votes as the GOP nominee in the 2012 election – was the only member of his party to vote for conviction, many of his colleagues who voted to acquit said Trump's actions were "inappropriate."

"His taking that stand, combined with all of the other remarks that different Republican senators had to say, there's no doubt what the president did was wrong," Clinton said. "It was to promote his own personal interests, not the interests of our country. It did put our national security at risk. Everything that was said was proven."

In a tweet later Wednesday, Clinton blasted the senators who voted for acquittal.

"As the president's impeachment trial began, Republican senators pledged an oath to defend the Constitution," she tweeted. "Today, 52 of them voted to betray that oath – and all of us.

"We’re entering dangerous territory for our democracy. It’ll take all of us working together to restore it."

Clinton told host DeGeneres that Trump "didn't think that anyone would hold him accountable" but that she hoped the voters would do just that in November.

"It's voters who are going to have to say, 'OK, I have to take responsibility for this and follow Mitt Romney's lead,'" she said.

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