One Democrat incumbent senator got some really terrible news yesterday, as Curt Anderson and Terry Spencer of the Associated Press report:

The midterm election next year holds the potential for the Republican Party to expand its slender two-vote majority in the Senate, despite the historical pattern of such elections punishing the party holding the White House. With 25 Democrat senators up for re-election, versus nine Republicans, the opportunities for pick-ups are there. But elections are fought one seat at a time.

A prominent Florida eye doctor accused of political corruption was convicted of Medicare fraud Friday, increasing the odds that federal prosecutors could pressure him to testify against New Jersey Democratic Sen. Bob Menendez. Dr. Salomon Melgen faces 15 to 20 years in prison on 67 counts, including health care fraud, submitting false claims and falsifying records in patients' files, unless he offers or accepts a deal before his sentencing, scheduled for July 14.

Senator Menendez has been indicted for allegedly accepting bribes from Dr. Melgen:

Melgen and Menendez face trial on Sept. 6 in New Jersey on charges the doctor bribed the senator for favors, including intervention in a billing dispute with Medicare.

If Dr. Melgen, who is 62 years old, does not want to die in prison, he may wish to turn state's evidence and testify against a sitting United States senator. That is the sort of target that can prompt prosecutors to offer serious leniency to a criminal. It is the food chain of stool pigeons.

If Senator Menendez is convicted and incarcerated, it would be up to New Jersey's incumbent Republican governor, Chris Christie, to appoint a replacement, who presumably would be a Republican, who then would be an incumbent in the 2018 November election.

Hat tip: Clarice Feldman

Deputy Editor Drew Belsky adds: New Jersey residents like this (former) one may remember that the "Christie appoints" scenario already came to pass once. After the death of Senator Frank "pro-lifers don't deserve freedoms in the Constitution" Lautenberg, Christie appointed Jeff Chiesa, New Jersey's attorney general, to fill the gap. Among the few votes Chiesa logged in during his four-month tenure was one for the "comprehensive immigration reform" bill floating around at the time.

Christie scheduled a special election as soon as humanly possible, whereupon now-senator Cory Booker cleaned out...a different person altogether. Chiesa did not bother to run.