Senator Collins was Wrong About the Law
Senator Collins in her floor speech carefully evaluated the judicial record of Justice Kavanaugh.
In her floor speech she made an objective argument regarding the judicial record of Justice Kavanaugh that was quite frankly a solid argument for confirmation from a purely academically qualified point of view.
However, the elephant in the room was Dr. Ford's testimony regarding a crime (sexual assault) and her eyewitness identification of Justice Kavanaugh, whom she knew from the country club they attended and identified "100%" as one of the two boys who assaulted her.
Senator Collins stated in her speech; "Mr. President, I listened carefully to Christine Blasey Ford's testimony before the Judiciary Committee. I found her testimony to be sincere, painful, and compelling. I believe that she is a survivor of a sexual assault and that this trauma has upended her life."
Essentially Senator Collins conceded that there was a crime. However, she rejected the eyewitness identification of a sincere and compelling witness because "the four witnesses she named could not corroborate any of the events of that evening gathering where she says the assault occurred". One of those witnesses was a co-defendant in the assault according to Dr. Ford and the others were drinking in another part of the house, unaware of the assault taking place upstairs. Additionally, the events took place over thirty-five years ago and it would be suspicious if the other people testified that they remembered a nondescript party.
Senator Collins also stated that the standards for a conviction in a criminal case of beyond a reasonable doubt would not be the standard she would follow, she would follow the standard of "more likely than not".
However, if it was a criminal case using the higher standard of beyond a reasonable doubt that resulted in a conviction, would the federal appeals courts uphold it based upon only the eyewitness identification of the Dr. Ford?
Yes. In a heartbeat.
If it was a criminal case appellate issues regarding jury instructions would be a likely attack by the defendant. If the jury was not instructed that "the identification testimony must be received with caution and scrutinized with care" under the facts of this case, would the conviction be overturned? No. Ironically the case decision in the circuit that includes the state of Maine that answers this question was United States v. Kavanaugh  decided in 1978!
In Kavanaugh the First Circuit held: "identification testimony may be treated as a statement of fact if the following circumstances are present: (1) the witness has had an opportunity to observe; (2) the resulting identification is positive; (3) the witness' identification is not undermined by a prior failure to identify or misidentification; and (4) the identification remains unqualified and certain after full cross-examination."
The law is clear that when eyewitness identification in a criminal case is made by a witness who knows the person they identified and is unqualified, it is enough evidence standing alone to convict someone beyond a reasonable doubt if the jury finds the witness to be credible. To put "credibility" in words used by Senator Collins, Dr. Ford was "a sincere, painful and compelling" witness.
At the end of the day the words of Senator Collins that "every person--man or woman--who makes a charge of sexual assault deserves to be heard and treated with respect" must be modified with "unless it can be supported by corroborating evidence".
The issue of "corroborating evidence" is complicated with the plethora of evidence that Justice Kavanaugh had a serious alcohol-consumption problem as a teenager and Dr. Ford telling friends and health-care professionals about the assault years before Justice Kavanaugh was nominated. Additionally, to me the most compelling corroborating evidence that supports that the assault took place was the remodel of Dr. Ford's home that included two front doors! 
In two years, Senator Collins who has a record of service that objectively she can be proud of as a normally thoughtful public servant must face reelection with perhaps the single most important issue her floor speech. Between now and then Justice Kavanaugh's judicial record will either support her evaluation of his judicial temperament or torpedo it.
However, criminal cases with eye-witness identifications by victims will take place with most of them under the radar of the public consciousness. The damage done by senators who patronize sexual-assault victims yet advance the theory that they should not be believed unless they come forward with corroborating evidence may take many more years to fully evaluate.