Donald Trump’s campaign has asked for personal information from more than a half-dozen possible vice presidential picks as the former president’s search for a running mate escalates.

The Trump operation’s decision to seek vetting records of potential candidates, which is typical for presidential nominees to request, shows that the former president has begun to zero in on a selection and resolve one of the biggest remaining questions of the 2024 race.

The requests went out to Ohio Sen. J.D. Vance, North Dakota Gov. Doug Burgum, South Carolina Sen. Tim Scott, Florida Rep. Byron Donalds, New York Rep. Elise Stefanik, Florida Sen. Marco Rubio, and former Housing and Urban Development Secretary Ben Carson, according to three people with knowledge of the deliberations who were granted anonymity to speak about internal matters.

The information requests were reported earlier by NBC News and ABC News.

On Tuesday night, Trump told Greg Kelly on Newsmax that he has “some unbelievable people” under consideration and proceeded to rattle off the names of some of his top surrogates including Scott, Burgum, Rubio, Vance and Carson.

One contender has seen their prospects fade, however: South Dakota Gov. Kristi Noem, who faced a firestorm after it emerged that she had written in a newly-published memoir that she had shot and killed her puppy. In the same book, she erroneously claimed she had met with North Korean dictator Kim Jong Un.

The former president has said there is a “good chance” he will announce his vice president pick around the time of the Republican National Convention in Milwaukee in mid-July. During the 2016 campaign, Trump announced then-Indiana Gov. Mike Pence just a few days before the start of the nominating convention.

“Anyone claiming to know who or when President Trump will choose his VP is lying, unless the person is named Donald J. Trump,” said Brian Hughes, a Trump campaign spokesperson.

Trump’s vice presidential contenders have been taking aggressive steps to distinguish themselves, such as doing interviews with national news outlets, fundraising for the former president and attending his hush money trial in New York.

Vance, a former venture capitalist, helped to organize a Silicon Valley fundraiser that Trump will be attending on Thursday evening. Scott, who is also trying to demonstrate his fundraising abilities, is scheduled to host a June 19 donor confab in Washington that is expected to draw major contributors.

Trump has been closely monitoring what the potential picks have been doing to help his campaign, according to a person familiar with the selection process, and he has continued to ask people around him for their opinion.

After Trump’s guilty verdict was handed down by a Manhattan judge last week, he asked some of his wealthiest donors for their ideas on who he should pick as his running mate. According to grocery store magnate John Catsimatidis, a Republican donor who was at the fundraising dinner, the top picks batted around by attendees included Scott, Burgum, former Secretary of State Mike Pompeo and former Trump primary rival Nikki Haley because she “might make the difference.”

Trump, however, has publicly said that Haley would not be his running mate.

CORRECTION: This story has been updated to correct Ben Carson’s former title.