Swing-vote senators face major political blowback, and potential high-profile challengers, after casting pivotal Kavanaugh votes

Several swing-vote senators are facing torrential political backlash for their stances on incoming Supreme Court Justice Brett Kavanaugh, as protesters and well-heeled political advocacy groups vow that Saturday's historic confirmation won't soon be forgotten.

On Saturday, President Trump predicted that Lisa Murkowski, R-Alaska, "will never recover" from her last-minute decision to become the only Senate Republican to oppose Kavanaugh.

“I think the people from Alaska will never forgive her for what she did," he told The Washington Post.

Murkowski announced her decision on Kavanaugh Friday after weeks of speculation, saying that despite being a "good man," Kavanaugh was "not the right man for the court" at the current moment.

But her vote was seen in conservative circles as a fundamental betrayal and a repudiation of basic principles of due process. Trump has made getting results on federal judicial nominees a key plank of his administration, and Senate Majority Leader Mitch McConnell, R-Ky., has led a successful push to install new conservative appellate and district court nominees at a record-breaking pace this year, with several more to be appointed in the coming weeks.

“I think the people from Alaska will never forgive her for what she did."

— President Trump

In response to Murkowski's vote, former Alaska Gov. Sarah Palin wrote on Twitter, "I can see 2022 from my house," in a tongue-in-cheek reference to "Saturday Night Live" actress Tina Fey's impersonation of her during the 2008 presidential election. The offhand remark set off a firestorm on social media, as some Republicans saw the possibility of a political comeback for Palin.

And Fox News host Laura Ingraham weighed in, writing, "I like Alaska...a lot. Maybe it’s time to run for Senate after all. ... Murkowski has abandoned all principles of due process and fairness. Disgraceful."

Ingraham added that Murkowski's speech "sounded like it was written by a Women's Studies' major at Wellesley [College]," a private women's school, and criticized its "abysmal delivery" and "pedestrian writing."

But there were several indications Murkowski would be relatively secure by the time she comes up for re-election in 2022. The longtime senator survived an upstart tea party primary challenge in 2010, and won by double-digits in her 2016 race.

Significantly more vulnerable is North Dakota Democratic Sen. Heidi Heitkamp, who voted against Kavanaugh after staying undecided for months. Fox News' polling shows Republican challenger Kevin Cramer now leading by 12 points (53-41 percent). Last month, before the Kavanaugh confirmation focused primarily on how to weigh the lurid and uncorroborated sexual misconduct allegations againts the nominee, Cramer was up by only 4 points (48-44 percent).

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Manchin, a red-state Democrat who didn't announce his support for Kavanaugh until after Maine Republcian Sen. Susan Collins' support already assured his confirmation, faced bitter, potentially career-ending backlash of his own from Republicans.

Manchin was the first Democrat to agree to meet with Kavanaugh on Capitol Hill, and he has repeatedly said that he wanted to carefully analyze the FBI's supplemental background check on Kavanaugh before casting his vote.

"A real profile in courage from Lyin’ liberal @JoeManchinWV," Donald Trump Jr. wrote on Twitter Friday. "Waited until Kavanugh had enough votes secured before he announced his support. I bet he had another press release ready to go if Collins went the other way."

He concluded with a call for West Virginians to elect Manchin's challenger, Republican Patrick Morrisey, in November: "Vote for #MAGA champion @MorriseyWV!"

Manchin faced even more hostile attacks from far-left progressives, who shouted and jeered at him as he walked through the Capitol complex under heavy security on Friday.

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Protesters also chanted "shame" at Manchin and drowned him out as he attempted to explain his vote in a televised interview.

In a dramatic address from the Senate floor Friday afternoon, Collins effectively provided political cover for Manchin's vote as she outlined for nearly an hour her reasons for supporting Kavanaugh, after carefully vetting his legal opinions, as well as the FBI supplemental background check into uncorroborated sexual misconduct allegations against him. The Maine Republican Party said the address was the "gold standard of speeches in explaining her vote and showing how a nominee should be evaluated."

In her speech, Collins decried the intense partisanship of the confirmation battle, and specifically noted that "interest groups have also spent an unprecedented amount of dark money opposing this nomination." Trump on Saturday called Collins an "honorable, incredible woman."

Within hours, one crowdfunding website, Crowdpac, said that it had crashed from the influx of donations intended to help Collins' eventual challenger. By Saturday afternoon, more than $3.2 millon had been raised for "her opponent's campaign, once that opponent has been identified." According to fundraising data from OpenSecrets.org, that number nearly matches the total amount raised this year by Maine's junior senator, Angus King, in his reelection bid.

Collins' announcement not only assured Kavanaugh's elevation to the Supreme Court, but also touched off an almost immediate uproar on Capitol Hill and across social media -- as well as among several well-heeled special interest groups.

Susan Rice, the former national security adviser to President Barack Obama, responded "me" on Friday to a post asking who could challenge Collins when she is up for re-election in 2020. She also retweeted a post slamming Collins' speech as a "paean to disingenuousness and incoherence."

Rice later clarified that she was "not making any announcements," but she said Collins' decision made her "deeply disappointed." She also re-posted another user who pointed out that "Rice's mother's family is from Maine and she has spent summers there." Rice is from Washington, D.C. and went to college at Stanford.

Arizona Republican Sen. Jeff Flake, another swing vote key vote for Kavanaugh, was pelted with expletives from protesters after announcing preliminary support for the nominee last week. He is retiring this year.

In Indiana, Democratic incumbent Joe Donnelly, who voted against Kavanaugh, currently tops Republican challenger Mike Braun by two points (43-41 percent), according to the latest Fox News polling.

Braun has said he would have supported Kavanaugh if he were in the Senate -- a stance backed by the state's other incumbent, Republican Sen. Todd Young.

Meanwhile, liberal advocacy group MoveOn announced it had canceled a six-figure advertising buy for Tennessee Gov. Phil Bredesen because of pro-Kavanaugh stance, even though Bredesen offers Democrats one of their best chances to win a Senate seat in November.