Washington (CNN) Jeff Sessions left the Senate for President Donald Trump. He might not make it back for the same reason.

The former senator from Alabama is "strongly considering" getting into the crowded race for his old seat, according to Politico . Republicans lost the seat in a 2017 special election -- following Sessions' confirmation as Trump's attorney general -- when the party nominated the deeply flawed candidate Roy Moore.

Now, Sen. Doug Jones is, by far, Democrats' most vulnerable incumbent running in 2020 -- and a slew of Republicans (including Moore) are lining up for the chance to be their party's nominee. No one has yet distinguished themselves, however, which has raised some concerns that Moore could eke out the nomination again, and again cost Republicans a seat.

Which is where Sessions comes in -- sort of. See, Sessions held the seat easily from 1996 to 2017. But he also got sideways with Trump -- or, more accurately, Trump got sideways with him -- during his time as attorney general. Sessions was subject to regular berating by the President via Twitter, and was fired the day after the 2018 midterm elections.

That, according to Rep. Bradley Byrne (R-Alabama), isn't something GOP primary voters are going to forget. "The President is very angry with Jeff," Byrne told The Washington Post this week . "I think the President will be very vocal against him. For Jeff's sake, I don't want that. But I think that's the reality of what he's facing." (Byrne told CNN's Manu Raju he has spoken with Sessions but refused to disclose what they talked about.)

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