Making huge inroads into metro Atlanta’s northern suburbs, Democrats gained 13 legislative seats in Tuesday’s election.

If the results hold — some of the races could have recounts — Tuesday will have marked the Democrats’ biggest legislative gains in about 20 years, according to election observers.

They picked up 11 seats in the House, where seven Republican incumbents appeared beaten, many in extremely close races. And ex-Democratic state Rep. Sally Harrell defeated longtime state Sen. Fran Millar, R-Dunwoody, while Democrats took the open seat being vacated by state Sen. David Shafer, R-Duluth.

Going into the election, Republicans held an advantage of 114-64 in the House, with two vacant seats, and 37-19 in the Senate. The results move the GOP further from an important goal: a two-thirds majority, which would allow them to approve proposed constitutional amendments without any Democratic votes.

There was always going to be big turnover in the General Assembly heading into the 2019 session because so many lawmakers retired or quit to run for higher office.

State Reps. Sam Teasley, R-MariettaBetty Price R-Roswell; Beth Beskin, R-AtlantaMeagan Hanson, R-BrookhavenScott Hilton, R-Peachtree CornersClay Cox, R-Lilburn; and Geoff Cauble, R-Locust Grove, all lost re-election bids. Democrats also picked up seats from retiring lawmakers in Gwinnett, north Fulton and Cobb counties.

"We're happy with the results," said state Senate Minority Leader Steven Henson, R-Stone Mountain. "We think this is the beginning of more pick-ups in the future."

A spokesman for state House Speaker David Ralston, R-Blue Ridge, said he didn't have a comment Wednesday on the election results.

While Republicans went into Tuesday hoping to regain seats lost in recent years and hold onto those where incumbents were quitting, Democrats sought to make inroads this year and in 2020 before lawmakers redraw political voter boundaries for the General Assembly and congressional districts following the once-a-decade census.

The General Assembly gets to pick its own districts, so the process could cement GOP control throughout the 2020s or give Democrats hope of eventually regaining the House and Senate. Republicans have run the state Senate since 2002 and House since after the 2004 elections.

Republicans had hoped to win back an Atlanta-area Senate seat taken in a special election last year by Democrat Jen Jordan. The post had been held by Hunter Hill, who quit to run unsuccessfully for the GOP gubernatorial nomination. Jordan prevailed handily Tuesday over Leah Aldridge, who was the top Republican vote-getter in last year's race.

The GOP had also hoped to keep a seat held for about 20 years by state Rep. Rich Golick in parts of Mableton, Smyrna and Vinings. Republican Matt Bentley faced Democrat Erick Allen in a race seen as a potential bellwether for suburban Atlanta, which has become increasingly competitive for Democrats in recent elections. Allen took the seat.

The Harrell-Millar Senate race was closely watched in an area that has been competitive of late.

Millar posted a farewell speech on Facebook on Wednesday congratulating his opponent and the Democratic Party.

“The Blue Wave struck North DeKalb, the Sandy Springs panhandle, and Peachtree Corners,” he wrote. “In January there will be no Republican in the DeKalb House or Senate delegation. I’m not sure what else I could have done to offset the anti Trump/Washington attitude and changing demographics. It has been an honor to serve our community for almost 20 years and I will continue posting through the balance of my term.”

Shafer, a Republican who ran unsuccessfully for lieutenant governor this year, hadn't faced any real opposition for his Gwinnett Senate seat in the past. But Lawrenceville attorney Zahra Karinshak, a Democrat, defeated Republican attorney Matt Reeves for the post Tuesday.

Two Athens-area seats won last year in special elections by Democratic state Reps. Deborah Gonzalez and Jonathan Wallace swung back to Republicans. The districts had been previously held by GOP lawmakers, and on Tuesday, Marcus Wiedower of Watkinsville beat Wallace, while Republican Houston Gaines — who lost to Gonzalez last year — beat her the second time around.

State House Minority Leader Bob Trammell, D-Luthersville, beat back a challenge in a district south of Atlanta from Republican Leonard Gomez, a former Grantville city councilman. Trammell said Gomez didn't live in the district, but the Secretary of State's Office rejected his attempt to kick the Republican off the ballot.

Further south, the last Republican lawmaker to represent a black-majority district won, as did a former GOP legislator who was hoping to regain the seat he lost in 2016.

Ex-longtime state Rep. Mike Cheokas, an Americus Republican, defeated Democrat Bardin Hooks, son of powerful former state Sen.George Hooks.

In far southwest Georgia, state Rep. Gerald Greene, R-Cuthbert, who has represented his district for 36 years, beat back the challenge of Democrat Joyce Barlow, a registered nurse from Dougherty County outside of Albany. Greene, who switched to the Republican Party in 2010, represents House District 151, which is 56 percent black.

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