The party may stick by him if he loses and becomes a convicted felony but voters that are voting for him because they think Biden is too old or they are unhappen with the economy, are saying they are not going to vote for a convicted felony.
There is also another issue. Will states allow him on the ballot for the general election if there contention that doing so violates the 14th amendment has been proven in court?
Federal election, state can't remove a candidate. Sorry.