While many in the Democratic Party admire her service — the idea of “country over party” has been central to Biden’s own political life and what inspired much of his successful presidential bid — there’s no clear consensus on how a Cheney candidacy could shake out. Some Democrats see the conservative congresswoman splitting the Republican vote, effectively breaking up the coalition around Trump and weakening him. In that scenario, these voices hope Cheney would hypothetically make Biden a stronger general election candidate, and her presence in the race would help make Trump a one-term president. Others, however, like Boyle, have...