“They’re trying to define the impeachment hearings as political before they begin. It helps fire up the base and tries to tint the testimony before it actually takes place,” said Republican strategist Ron Bonjean…

Aides and strategists say the aim of the push to unmask the whistleblower is to deflect voter attention away from impeachment testimony and cast doubt on the Democratic-led proceedings.

“Republican voters want to stick with their tribe and defend the president, and they need something to go on. This gives strong Trump voters something to say when the actual request to Ukraine is indefensible,” said Republican strategist Rory Cooper, who was a top aide to former House Speaker Eric Cantor.

The Republican Party official said internal polling shows that large numbers of voters view the impeachment investigation as politically motivated.