"Little children, it is the last time: and as ye have heard that antichrist shall come, even now are there many antichrists; whereby we know that it is the last time. (1 John 2:18)
Who is a liar but he that denieth that Jesus is the Christ? He is antichrist, that denieth the Father and the Son. (1 John 2:22)
And every spirit that confesseth not that Jesus Christ is come in the flesh is not of God: and this is that spirit of antichrist, whereof ye have heard that it should come; and even now already is it in the world. (1 John 4:3)
For many deceivers are entered into the world, who confess not that Jesus Christ is come in the flesh. This is a deceiver and an antichrist. (2 John 1:7) "
So, if all this is correct, the concept of one specific anti christ is a no brainer. Then of ocurse, if there are already anti christs around, why do some insist in believing in the locusts and rapture etc and the coming of one specific antichrist to lead the world to doom?
Personally, i find the idea that the roman catholic church is the anti christ interesting, it does follow logically from the description given in revelations about the beast etc etc.