Republicans came out of the 2016 elections controlling every legislative chamber in the South. But this year, with a handful of off-year elections in play, Southern Democrats rode a progressive wave to come within striking distance of winning a majority in the Virginia House of Delegates and picked up three seats in the Georgia legislature.

Analysts and pundits are still divining the lessons of 2017, including the answer to a key question that will shape Southern politics for more than a decade: Where can Democrats win control of Southern legislatures by 2020, when lawmakers will redraw political maps after the census count?

The successes of 2017 certainly offer Democrats grounds for optimism.

In Virginia, where voters cast ballots for all 100 members of the House of Delegates, Democrats controlled only 34 seats heading into the 2017 elections. After Election Day, they had picked up 15 seats. Republicans currently cling to a 51-49 majority, although three of the races are still too close to call and will be decided by lawsuits and recounts. In Virginia House District 94, which includes Newport News, the GOP candidate is currently ahead by a mere 10 votes.

Gerrymandering and the balance of power

In many other Southern legislatures, Democrats are within the same striking distance — or even closer — to taking power as Virginia Democrats were coming into the 2017 elections.

A Facing South/Institute for Southern Studies analysis of the balance of power in the South's 26 legislative chambers finds that in more than half (14), Democrats currently hold 34 percent or more of the seats, giving them an equal or lesser margin than the party closed in 2017 in the Virginia House.

Of course, not every state in the South is like Virginia, a blue-trending state that has voted Democratic for president the last three elections and where seven of the last 10 gubernatorial contests have been won by a Democrat.

Indeed, the ability of Republicans to maintain control of the Virginia legislature this decade was largely due GOP-friendly maps drawn up in 2011, which diluted Democratic voting strength in most districts ("cracking") while giving them hyper-majorities in others ("packing").

Partisan gerrymandering helped Virginia Republicans limit the damage again in 2017. While the House of Delegates is currently almost evenly split between Democrats and Republicans, across the state Democratic candidates received about 220,000 more votes than their Republican counterparts, a 10-point advantage.

If the House election results mirrored the partisan choices of Virginia voters, Democrats would enjoy a 54-44 majority. When Virginia holds its next round of legislative elections in 2019, Democrats may not enjoy the same upswell of Democratic sentiment that brought them to a near-draw in the state's lower chamber. As election law expert Nicholas Stephanopoulos wrote in the Los Angeles Times: