Dave Sharma has promised to fight for Australia's national security in a time of global turmoil as he prepares to re-enter federal parliament.
Liberal Party members in NSW have picked Mr Sharma to replace former foreign minister Marise Payne, who has retired from the Senate.
He beat former NSW minister Andrew Constance, a frontrunner backed by Opposition Leader Peter Dutton.
Also defeated were former ACT senator Zed Seselja and fellow conservative Monica Tudehope.
Mr Sharma, who represented the Sydney seat of Wentworth until his defeat at the 2022 election, denied any friction with the party leader, saying he and Mr Dutton had a good relationship.
"I've got absolutely no problems working with him and with other members of the Liberal parliamentary team," he told ABC radio on Monday.
Mr Sharma promised to hold the Albanese government to account and fight for struggling families, while also pursuing international issues.
Fellow Liberal moderate Andrew Bragg welcomed Mr Sharma's return to federal politics, saying he would be "a formidable and feared senator".
"He has inside information about a lot of key security and national interest matters, which I think will make him a very successful, long-serving senator," he told AAP.
Asked whether Mr Sharma being voted in after another NSW moderate Maria Kovacic was selected for the Senate meant they could push harder to enact change in policy areas such as climate change, Senator Bragg said too much focus was placed on factions.
"I know the media get interested in these labels but we're the Liberal Party, it's one party," he said.
"We obviously think that the issue of climate change is very important across the board.
"I'm very pleased that we are sticking to (net-zero emissions by 2050) because that will be the right economic and environmental outcome for the country."
A large number of inner city moderates lost their seats at the last election to 'teal' independents campaigning heavily on climate change, Mr Sharma included.
Before entering parliament, he was the Australian ambassador to Israel.
Mr Dutton said his return to federal politics came at a crucial time and his diplomatic and foreign policy expertise would "lend considerable weight and wisdom to the public policy debate".
In another vote on Sunday, former state Liberal president Greg Mirabella was defeated in his quest for third spot on the coalition's Victorian Senate ticket.
Mr Mirabella was considered favourite to claim the last winnable spot for the next election and was Mr Dutton's preferred pick.
But rank-and-file Victorian Liberal members instead chose small business owner and former Baptist pastor Kyle Hoppitt.
Mr Mirabella, the husband of former Howard government minister Sophie Mirabella, stepped down as party president to make the preselection tilt after missing out at the last election.
State opposition leader John Pesutto threw his weight behind former Victorian Chamber of Commerce and Industry president Karyn Sobels, who did not make the final round of voting.
He denied the result was a reflection of his authority as state Liberal leader.
