The two will hold dueling events in Arizona on Friday as they stump for rival candidates who offer dramatically different visions of the Republican Party in a critical battleground state. Days later, they will once again cross paths as they deliver major speeches on the same day in Washington, D.C.

The encounters mark a more confrontational phase in the fraught relationship between the former running mates and once close confidantes who could soon find themselves competing against one another in the 2024 GOP presidential primary if they both ultimately choose to run.

"I think this is a continuation of the larger message that Pence is trying to embody here, which is the Republican Party should look to the future," said Scott Jennings, a longtime party strategist. "This is going to be the existential question for the Republican Party: Are we going to listen to a slightly different view than Donald Trump's? Right now, the standard-bearer for this is Mike Pence."