Balz at WaPo:

Republican officials have rhetorically brushed aside President Trump’s refusal to say he will accept the results of the election. They note that presidencies have changed hands peacefully since the start of the republic. Meanwhile, they are engaged in a systematic effort to make voting more difficult.

These actions are not the work of a confident, expanding party; they are not signs of a party that sees its coalition growing and its appeal widening. Instead, they are an acknowledgment that, unless something changes, they could face a bleak future, one in which winning elections will depend more on holding down the size of an increasingly diverse electorate than on encouraging the widest possible enfranchisement.

This is not a new phenomenon. For some years, Republicans at the state level have instituted barriers to voting. They have done this in the name of ballot integrity, despite the absence of evidence of widespread fraud in voting.