What is the test for misconduct in a federal criminal case when a federal prosecutor makes comments to the jury during closing argument?

A prosecutor's conduct violates the federal Constitution only if it is so egregious, and infects the trial with such unfairness, that the resulting conviction is a denial of due process. (People v. Smithey (1999) 20 Cal.4th 936, 960.) Conduct that does not constitute such fundamental unfairness is misconduct under state law only if it involves "'"the use of deceptive or reprehensible methods to attempt to persuade . . . the jury."'" (People v. Benavides (2005) 35 Cal.4th 69, 108.) During closing argument a party has broad discretion to argue the evidence vigorously and to comment on reasonable inferences that may be drawn therefrom. (See People v. Bemore (2000) 22 Cal.4th 809, 846.) To prevail on a claim of prosecutorial misconduct based on remarks to the jury, the defendant must show not only prejudice but also a reasonable likelihood the jury understood or applied the complained-of comments in an improper or erroneous manner. (See People v. Ayala (2000) 23 Cal.4th 225, 283-284; People v. Frye (1998) 18 Cal.4th 894, 970.)