Nikki Haley received roughly 20,000 Election Day votes over Trump in the Georgia GOP primary after dropping her White House bid. Why it matters.

• With no major GOP opponents, ex-President Donald Trump easily won the Georgia primary on Tuesday.
• But Nikki Haley still won roughly 20,000 Election Day votes despite her exit from the WH race.
• Trump's softest margins in the state were in metro Atlanta, the nexus of recent GOP struggles.

Former President Donald Trump romped in the Georgia Republican presidential primary on Tuesday en route to surpassing the 1,215-delegate mark needed to secure the GOP nomination.

But the Georgia results showed that former South Carolina Gov. Nikki Haley still left a notable mark in the race, despite ending her candidacy last week after being swamped by Trump on Super Tuesday.

While Trump won the Georgia primary with about 84.5 percent of the vote compared to Haley's 13 percent, the former president's weakest performances were centered in the Atlanta metropolitan region, the nexus of his electoral troubles in the 2020 election.

Statewide, Haley won about 78,000 votes in the GOP primary. And roughly 20,000 of those votes were cast on Election day, according to The Atlanta Journal-Constitution.

This occurred after the former UN ambassador had already left the race.

Looking ahead to November, why does this matter?

GOP suburban erosion

Trump's polarizing 2016 presidential bid led some moderate Georgia Republicans to back Democrats at the top of the ballot. And they continued backing Democrats in the 2018 midterms, while also voting for Joe Biden in 2020 and Democrats Raphael Warnock and Jon Ossoff in the 2021 Senate runoff elections.

In 2022, many of these voters backed Warnock over Republican Herschel Walker in the marquee Senate election and runoff contest while also backing GOP Gov. Brian Kemp's reelection bid over Democrat Stacey Abrams. Warnock and Kemp both explicitly sought to appeal to Independents while also courting their respective party bases, which was the winning formula for both men that year.

The common denominator of GOP suburban erosion across the Atlanta area has been the Trump factor, with the former president proving to be an unpopular fit with the social moderation of many party voters in Cobb, DeKalb, Fulton, and Gwinnett counties — despite many of them holding conservative views on fiscal matters.

Despite winning Georgia by more than 71 percentage points in the primary, Trump only carried Fulton — which contains most of Atlanta and many of its affluent northern suburbs — by 21 percentage points (59%-38%). In DeKalb, the margin was 16 percentage points (56%-40%).

Trump performed much better in Cobb (74%-23%) and Gwinnett (80%-17%), but the numbers in those jurisdictions were still short of his statewide percentage.

Biden will almost surely win DeKalb and Fulton in the general election, and if Cobb and Gwinnett also go for the president by a significant margin, Trump will have to hope his rural and exurban margins can compete with any Democratic edge.

The ghost of the 2020 election still lingers

In the 2020 election, Biden won Georgia by a 0.23% margin, or roughly 12,000 votes out of roughly 5 million ballots cast.

Trump immediately contested the results, pointing to alleged voter fraud that could not be substantiated and pressuring Kemp and GOP Secretary of State Brad Raffensperger to help overturn the election.

Both men refused to entertain Trump's entreaties, leading to years of attacks from the ex-president against the Peach State Republicans.

In 2022, Trump's hand-picked candidates to run against Kemp and Raffensperger in the GOP primary lost handily, and both men won reelection later that year.

With Biden and Trump now set for a rematch this year, Georgia is again one of the most coveted swing states on the presidential map.

And the race is happening in the midst of a key election interference case in Fulton County, where Trump faces a raft of charges over his actions to affect the outcome of the 2020 race in Georgia.

College-educated voters across the country had already been moving away from Trump and helping dilute GOP strength in suburbs where the party once dominated the political scene.

So the roughly 20,000 voters who backed Haley across the state on primary day will play a huge role in November, as they could support Biden, pull the lever for Trump, choose a third-party candidate, leave the top of the ticket blank, or stay at home.