Gov. Josh Shapiro, Sen. Mark Kelly said to be leading VP candidates for Harris

After President Joe Biden's decision to drop out of the 2024 presidential race on Sunday, Vice President Kamala Harris has emerged as the party favorite to replace him at the top of the ticket.

The vetting process has begun for who will be Harris' running mate.

A senior administration official told ABC News' Martha Raddatz that Pennsylvania Gov. Josh Shapiro and Arizona Sen. Mark Kelly are the leading candidates to be Harris' running mate.

The two men come from key 2024 battleground states and have experience trouncing Trump-endorsed candidates.

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Shapiro, 51, was Pennsylvania's attorney general before being elected governor in 2022 after defeating Republican Doug Mastriano.

Kelly, a 60-year-old former astronaut and Navy captain who is married to former congresswoman Gabby Giffords, won his Senate seat in 2022. He defeated Republican challenger Blake Masters.

Other potential candidates

Other potential VP candidates include Michigan Gov. Gretchen Whitmer, North Carolina Gov. Roy Cooper, New Jersey Gov. Phil Murphy, Kentucky Gov. Andy Beshear, Maryland Gov. Wes Moore and Illinois Gov. J. B. Pritzker.