She will not drop from the race unless she drops dead or goes into a irreversible coma and is removed by the DNC. These folks quest for power and control is extreme.
Since she is viewed more favorably than Trump by Wall Street there will be a good selloff, but the market will bounce back once Biden is announced as her replacement. If she croaks after the debates but before the election her cabal will secretly keep her on life support and out of site until after the election. They will attempt to keep this going until Scully and Mulder expose them, but it will still take intervention by the courts to oust her since the Dems in Congress won't see this as a problem and refuse to vote for impeachment.