NORFOLK, Va. (AP) — Republican presidential candidate Mitt Romney tapped Rep. Paul Ryan of Wisconsin as his vice presidential running mate for the fall campaign on Saturday, turning to the architect of a conservative and intensely controversial long-term budget plan to remake Medicare and cut trillions in federal spending.

Romney made his announcement to supporters via a phone app.

“Mitt’s Choice for VP is Paul Ryan,” it said and implored backers to spread the word.

The ticket-mates arranged their first joint appearance later in the morning at a naval museum, first stop of a bus tour through four battleground states in as many days.