Sarah Riggs Amico will have to wait two months before she learns who she will face in November’s race for lieutenant governor.

The Marietta Democrat beat out small-business owner Triana Arnold James in Tuesday’s primary election. Both women were first-time candidates.

State Sen. David Shafer and former state Rep. Geoff Duncan will face off again in July as they battle for the Republican nomination.

Shafer, a Duluth resident, has served 16 years in the Senate, five of them as the Senate president pro tempore.

Shafer said if elected, he would continue work to lower the state’s income tax rate. The General Assembly this year approved lowering the state’s top income tax rate from 6 percent to 5.5 percent.

Duncan said the politics of lawmaking needs to be changed. The Cumming resident, who likes to position himself as an outsider, served five years in the state House before resigning last year to focus on his campaign.

Duncan said if elected, he would put an end to legislative horse trading.

Amico, who is the executive chairwoman of a transportation company, touts her business experience as the reason Georgians should vote for her.

The winner of the July 24 runoff will face Amico in November.