They believe he is their savior. The Bible says "Believe on the Lord Jesus Christ, and thou shalt be saved, and thy house." It doesn't say believe he is God equal and coeternal with the Father, just that God [sic] raised him: "If thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved."
The Bible also says "For whosoever shall call upon the name of the Lord shall be saved" or obey Jesus "And [Jesus] being made perfect, he became the author of eternal salvation unto all them that obey him," or keep his saying "If a man keep my saying, he shall never see death" or just by his name "Neither is there salvation in any other: for there is none other name [besides Jesus'] under heaven given among men, whereby we must be saved," etc, etc. etc.
A person has to know whose name they are calling upon if it is to mean anything.
There are plenty of people who say “Lord, Lord!” but they don’t know Christ and thus Christ will tell them to depart because He “never knew them.”
To know Christ is to recognize that He is not just Godly, but that He is God.