Republicans would need control of at least 34 state legislatures to be able to call such a convention, and 37 to ratify any amendments.
So far they have unified control of 31 state legislatures. Of those 31, 19 have signed onto an application for an Article V Convention put forward by Convention of States, a conservative activist group.
https://www.businessinsider.com/constitutional-convention-conservative-scholar-states-2022-8
https://www.businessinsider.com/constitutional-convention-conservatives-republicans-constitution-supreme-court-2022-7
If the GOP gets to re-write the constitution then Balkanization would be one of the better possible outcomes.