The Republican primary campaign for Georgia governor will go to a June runoff, with the lieutenant governor Burt Jones facing off against healthcare billionaire Rick Jackson – and locking out Brad Raffensperger, the Georgia secretary of state and longtime political enemy of Donald Trump who was on track to finish a distant third.

The Republican race to challenge the US senator Jon Ossoff remains similarly unresolved, while former Atlanta mayor Keisha Lance Bottoms won the Democratic primary for governor outright.

Meanwhile, two Georgia supreme court justices won re-election, fending off Democratic-backed challengers former state senator Jen Jordan and personal injury attorney Miracle Rankin.

Judicial elections in Georgia are nonpartisan and decided on primary election ballots. The Georgia supreme court has no Democrat serving on it, because primary elections typically have had lopsided Republican turnout. The court is currently considering the constitutionality of a six-week “heartbeat” abortion ban, which added subtext to the race. The race has been heavily advertised and promoted online in ways that have historically been unusual for a judicial race in Georgia.

The judicial contest has at times overshadowed the race to replace the outgoing Republican governor, Brian Kemp. Polling over the last month suggested that a runoff in the well-contested Democratic field was widely expected, with Bottoms, who was endorsed by Joe Biden, finishing in first place. But Bottoms took a wide lead shortly after polls closed, according to preliminary results from the Associated Press, securing the Democratic nomination.

The Democratic primary was relatively genteel compared to dueling attack advertising among Republicans. Jones, who has been endorsed by Trump, and Jackson will continue their showdown, which has soaked up almost all of the available advertising inventory on Georgia television.

Jackson, a political newcomer who was relatively unknown in the state, nevertheless upended the contest by pouring nearly $50mn of his own money into campaign advertising. Republican candidates spent more than $100m in total, according to tracking figures from AdImpact.

A long-time Republican stronghold, Georgia has emerged in recent years as a consequential swing state. The state narrowly voted for Biden in 2020, and Democrats occupy both of the state’s US senate seats. The open race for governor is considered one of the most competitive in the country.

Senator Ossoff had no Democratic primary challenger, and is sitting on more than $30m heading into the November election. Mike Collins emerged from a crowded Republican primary contest Tuesday as the top vote-getter to challenge Ossoff. He will face Derek Dooley, a former University of Tennessee football coach who was endorsed by Georgia’s governor, in the 16 June runoff.