2024 Senate Elections in Play?

 1.  Arizona, with Sinema to be challenged in the Democratic primary, and seriously challenged by a GOP contender.

2.  Michigan.  Incumbent retiring.  

3.  Montana.  Currently near 50-50 split. Tester (D) might face a serious challenge this time.  

4.  Nevada.  Rosen (D) to be openly challenged. Near 50-50 split.

5.  Ohio.  Brown (D) to be fairly challenged.  Near a 50-50 split.

The rest would all likely be won by incumbents. Roughest race is Arizona, with Sinema (D) likely defeated by the Democratic challenger in the primary.  Maricopa County would be unable to repeat the gimmicks of 2022, with printers 'acting up'.   

I would guess two Republican wins in the five states...giving a slight edge to the Republicans.