If Mark Kelly becomes Democrats' vice presidential nominee, who would replace him in the Senate?

Speculation that U.S. Sen. Mark Kelly may be a vice presidential pick is having a trickle-down effect in Arizona, leading many to wonder who could replace him if he resigns the swing-state Senate seat.

Appointing a replacement for Kelly, D-Ariz., in the U.S. Senate would fall to Gov. Katie Hobbs, a fellow Democrat. But a vacancy would likely not happen for months and would only happen if several monumental things fall into place — including, foremost, Kelly's name emerging as the top pick to run with presumptive Democratic nominee Kamala Harris. After that, the Harris-Kelly ticket would have to win in November.

President Joe Biden's shocking Sunday announcement that he would step out of the race for the White House quickly saw Democrats coalescing around Harris, the vice president, as their nominee. But who will become her running mate is not yet determined.

Kelly's is one of several names that have been discussed.

When would a Senate vacancy happen?

Just like GOP nominee Donald Trump's vice presidential pick, Sen. JD Vance, R-Ohio, Kelly would not have to resign to run.

If Kelly or Vance followed the footsteps of many senators-turned-vice presidents before them, they would do so after a win in November.

There's precedent for that resignation to happen even later, in January, just days before being sworn in. Both Biden and Harris were U.S. senators before they were elected vice president in 2008 and 2020, respectively, and both resigned their Senate seats in January of the following year.

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Hobbs’ official spokesperson and her chief political strategist declined to comment about the possibility the governor could pick a replacement for Kelly in several months.

But after 14 years serving in public office in Arizona, Hobbs' priorities can be found in her public résumé. Here are the qualities Hobbs might consider, and the possible candidates whose names are being floated by observers from both major parties.

What might Gov. Katie Hobbs consider in picking a Kelly replacement?

She would surely face pressure from Democratic groups in Washington, D.C., to pick a successor who could win a full term in the next election, not wanting to risk turnover of a battleground state Senate seat in what will likely remain a closely divided chamber.

Hobbs may look to name a senator whose identity reflects her pledge to make Arizona more equitable for diverse communities.

Hobbs ran for governor in 2022 pledging to build an inclusive administration, releasing a 15-point plan that was in part a response to criticism that she mishandled a race and gender discrimination case. A Black state Senate aide twice won the case over her firing that happened when Hobbs was the Senate leader.

As governor, Hobbs hired a diversity, equity and inclusion director and delivered the first State of the State speech to tribal leaders. She has expanded a state office that coordinates tribes and state government services.

Arizonans have never sent an Indigenous person to the U.S. Senate, nor a Latina woman, two potential firsts that may appeal to Hobbs if she gets to choose a senator.

Who might Hobbs consider?

A handful of names have risen to the top as rumors swirl about whom Hobbs might pick. A couple are believed to be possible candidates to run with Hobbs in 2026, when she will be the first Arizona governor to campaign with a lieutenant governor.

Arizona Corporation Commissioner Anna Tovar made state history when she was elected to the role regulating utilities in 2020.

She and Republican Lea Márquez Petersen were both elected that year, becoming the first Latinas to win statewide office.

Tovar, the only Democrat on the commission, is not running for reelection this year. A former schoolteacher, she was named by Hobbs in October to a seat on the State Board of Education. Tovar previously was a state lawmaker who served in the Legislature at the same time as Hobbs.

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Tucson Mayor Regina Romero, the city’s first female and first Latina mayor, may also be on the shortlist. Romero is the daughter of immigrant farmworkers and was previously on the Tucson City Council. She has had several appearances with Hobbs since 2022.

Another possibility is Stephen Roe Lewis, the three-term governor of the Gila River Indian Community south of Phoenix. Lewis and Hobbs have worked closely together, notably on water conservation and infrastructure issues. Lewis was a featured speaker at Hobbs' inauguration, and Hobbs named Lewis to her Water Policy Council last year.

Other Kelly successors could include U.S. Rep. Greg Stanton, a former mayor of Phoenix; Hobbs’ chief of staff and former lawmaker Chad Campbell; Attorney General Kris Mayes; and Phoenix Mayor Kate Gallego.

This list of contenders could change significantly depending on other races on the ballot this November.

Hobbs might have a strong option if Democratic U.S. Rep. Ruben Gallego, who is running for the Senate seat held by Sen. Kyrsten Sinema, I-Ariz., loses.

Election predictors like Sabato’s Crystal Ball rate the Senate race as leaning in Democrats’ favor, and Arizona voters have already once rejected the GOP front-runner, former news anchor Kari Lake, in a statewide race. Lake lost to Hobbs in 2022 by about 17,000 votes.

Ruben Gallego is a former Marine and a five-term member of Congress representing south Phoenix and the southwestern Valley.

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Reach reporter Stacey Barchenger at stacey.barchenger@arizonarepublic.com or 480-416-5669.

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This article originally appeared on Arizona Republic: Who would replace Kelly in Senate if he is vice presidential pick?