As you say, this is a complex issue. Kamala Harris will not win the presidency if she does not support the bipartisan bill that Trump killed--the bill that also provides a path toward citizenship for some migrants. She will lose because Trump's lies have been successful enough so that a majority of the American people want to restrict immigration. The people will not vote Democrat unless there is a promise that immigration will be restricted. If Harris does lose to Trump, the border will be shut down and 11 million immigrants will be deported (according to what is in this platform and everything he has said about this). This will lead to many, many more deaths at the border and, additionally, in the U.S.