Guttenberg's 14-year-old daughter, Jaime, was among 17 people killed on February 14 at Stoneman Douglas High School in Florida. As part of their effort to stop that from happening, opponents of the judge are targeting Collins as the most likely Republican to vote against his confirmation.
The spotlight on Collins and Sen. Kavanaugh's testimony did not appear to have cost him any support among Republicans, nor has it prodded two moderates in the caucus to declare how they will vote.
The latter point stems from allegations Collins made to The Wall Street Journal that someone had left a voicemail with one of her state offices in which "they actually threatened to rape one of my young female staffers".
"There's some very abusive callers that we've had, some very vulgar calls and sort of harassing the staff", Steve Abbott, Collins' chief of staff, said, according to Portland, Maine, NBC affiliate WCSH.
Here are five US senators who could either make or break Kavanaugh's nomination. "Threats or other attempts to bully her will not play a factor in her decision-making whatsoever", said Annie Clark, a spokeswoman for Collins. As of Wednesday, it had raised 90 percent of its $1,302,388 goal.
King spoke Tuesday at a rally outside her Anchorage office, saying she shouldn't bow to President Donald Trump. Members of the group have met with Collins over the past 18 months on issues such as protecting the state's young immigrants known as Dreamers.
In his confirmation hearing last week, Kavanaugh would not commit to upholding the provision of the health-care law that protects coverage for consumers with preexisting conditions.
As he had during the hearings, Kavanaugh declined to weigh in on what exceptions he would allow should Roe v. Wade be overturned, citing judicial independence.
The activists have stated they intend to return the funds to donors if Senator Collins votes against Mr Kavanaugh.
Collins told the conservative news site Newsmax that she sees this as "quid pro quo fundraising" and "the equivalent of an attempt to bribe me to vote against Judge Kavanaugh". "And it is extraordinary to me that people would want to participate in trying to essentially buy a Senator's vote".
Follayttar described the effort as a grassroots mobilization made up of smaller-dollar pledges.
Senator Collins ran for Congress on a platform of being both pro-choice and someone who would prioritise the needs of her constituents over her party.
"We won't let it stifle us".
"I am pleased to say", Ms. Collins says with a small chuckle, "we had a group that has a thrift shop that helps low-income women ask us for 300 of the hangers. Kavanaugh, accusing the longtime appeals court judge of misleading or even lying under oath during his confirmation hearing last week".
Democrats accused Republicans of seeking to ram the confirmation through without a thorough vetting before the November midterm elections.
After over an hour of debate and almost 5 different Democratic motions pertaining to the Kavanaugh confirmation, regular business resumed for the committee who voted on the confirmation of 13 other lower court judges and USA attorneys.