Can a defendant be found guilty of aiding and abetting a crime?

"Under 18 U.S.C. 2, a defendant may be convicted of aiding and abetting a given crime where the government proves that the underlying crime was committed by a person other than the defendant, that the defendant knew of the crime, and that the defendant acted with the intent to contribute to the success of the underlying crime." United States v. Hamilton, 334 F.3d 170, 180 (2d Cir. 2003). A conviction under 2 requires sufficient proof that the defendant knowingly and willfully participated in the offense in a way that showed he intended to make it succeed.