Yes, electronic voting machines are more succeptible to fraud than other types of voting machines because unlike other types of voting machines, electronic voting machines may leave no sign of tampering. If something is easier to tamper with, then it is more likely to be tampered with. Thus, the problem the US has had with electronic tampering.
Electronic Voting machines are more susceptible to fraud simply because the data can be stored on such a smaller scale. This inevitably leads to an easy to hide form of fraud. In the old paper days in order to skew one hundred thousand votes, you would need one hundred thousand ballots filtered into many voting locations. In the electronic world that information can be put onto a small disc drive and easily used to register as many votes as you want on any machine that you want.