Libertarian vice presidential candidate Bill Weld — in a striking split from running mate Gary Johnson — said Tuesday night he was "vouching" for Democratic nominee Hillary Clinton.
While he stopped short of telling people to vote for her, Weld acknowledged that his party might only muster 5 percent of the popular vote — and he fears for what would happen if Republican nominee Donald Trump won on Election Day.
RELATED: Don't forget to hit the polls on November 8th
"I know her well personally," Weld, a former Republican governor of Massachusetts, said of Clinton on MSNBC's "The Rachel Maddow Show." "I know her to be a person of high moral character, a reliable person and an honest person, however so much Mr. Trump may rant and rave to the contrary. So, I'm happy to say that, and people can make their own choices."
Johnson has attacked both Trump and Clinton, and said last week that he thinks Clinton could ultimately be impeached over the FBI review of her emails.
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Gary Johnson through the years
Gary Johnson through the years
UNITED STATES - MARCH 3: Gov. Gary Johnson, former Governor of NM, speaks at the American Conservative Union's CPAC conference at National Harbor in Oxon Hill, Md., on Thursday, March 3, 2016. (Photo By Bill Clark/CQ Roll Call)
UNITED STATES - FEBRUARY 26: Former New Mexico Gov. Gary Johnson pretends to have a heart attack on stage while arguing in favor of legalization of marijuana during CPAC in National Harbor, Md., on Feb. 26, 2015. Former Rep. Ann Marie Buerkle, R-N.Y., not pictured, had just argued during their debate that marijuana caused an increased risk of heart attacks. (Photo By Bill Clark/CQ Roll Call)
ORLANDO, FL - SEPTEMBER 22: Former New Mexico Gov. Gary Johnson speaks in the Fox News/Google GOP Debate at the Orange County Convention Center on September 22, 2011 in Orlando, Florida. The debate featured the nine Republican candidates two days before the Florida straw poll. (Photo by Mark Wilson/Getty Images)
File-This Nov. 3, 2011 file photo shows former New Mexico Gov. Gary Johnson addressing the 2011 Drug Policy Alliance conference in Los Angeles. On Tuesday, July 1, 2014 it was announced that Johnson had been named the CEO of a Nevada-based company that hopes to make medical and recreational marijuana products. (AP Photo/Damian Dovarganes, File)
Gary Johnson, the Libertarian Party candidate for president, addresses an audience of students and the public at Macalester College, Friday, Sept. 21, 2012 in St. Paul, Minn. Johnson, a former two-term New Mexico governor, is on a nationwide college tour as part of his campaign for president. (AP Photo/Jim Mone)
Republican presidential candidates, from left, former New Mexico Gov. Gary Johnson, former Pennsylvania Sen. Rick Santorum and former House Speaker Newt Gingrich, prepare prior to a debate Thursday, Sept. 22, 2011, in Orlando, Fla. (AP Photo/John Raoux)
FILE - In this Sept 23, 2011 file-pool photo, former New Mexico Gov. Gary Johnson speaks in Orlando, Fla. The Libertarian Johnson is running for president a second time after winning more than a million votes in 2012. (AP Photo/Joe Burbank, Pool, File)
Former New Mexico Gov. Gary Johnson announces his plans to seek the Republican nomination for president in front of the Statehouse Thursday, April 21, 2011 in Concord, N.H. Gov. Johnson says he has the resume needed to lead the country. (AP Photo/Jim Cole)
New Mexico Gov. Gary Johnson, shown at the Inn of Loretto, Wednesday, Feb. 3, 1999, in Santa Fe, N.M. Insurance companies that back a ``no pay, no play'' proposal, promoted by Gov. Gary Johnson, say they would save money if uninsured drivers were barred from making big claims. Under the legislation, insurance companies would be required to file new rates taking into account their anticipated savings from the new law in August. (AP Photo/Laura Husar)
Texas Gov. George W. Bush, left, makes a joke about the first time he met New Mexico Gov. Gary Johnson, right, as he addresses a crowd at a barbecue June 19, 1998, in support of Johnson's re-election campaign in Albuquerque, N.M. (AP Photo/Jake Schoellkopf)
New Mexico Governor Gary Johnson enters the Roswell Convention Center Thursday, July 3, 1997 surrounded by aliens. The governor and his family visited Roswell to participate in the 50th anniversary celebration of eth Roswell incident.(AP Photo/Susan Sterner)