Described as "extraordinarily crafty and unquestionably persistent on the stump," Barrow survived several tough reelection bids in an increasingly Republican district.

However, Republican college professor Max Burns had unexpectedly won the seat in 2002 because of ethical questions surrounding the Charles "Champ" Walker, Jr., the Democratic nominee that year.

One of their first acts was a rare mid-decade redistricting that targeted Barrow and the other white Democrat in the Georgia delegation, Jim Marshall.

Barrow faced Burns in the general election and won by only 864 votes — the narrowest margin of any Democratic incumbent nationwide.

However, he trounced Burns in Chatham and Richmond counties — home to Democratic-leaning Savannah and Augusta, respectively (as well as more than half the district's population) — by a total of over 17,000 votes.

Barrow's 2006 candidacy faced not only the mid-decade redistricting but also two visits by President George W. Bush to the district, campaigning by national figures on behalf of Burns (including RNC Chair Ken Mehlman and U.S. Speaker of the House Dennis Hastert) and popular Governor Sonny Perdue's reelection bid.

[12] Barrow drew a primary challenge from state Sen. Regina Thomas in 2008, who argued that the congressman voted too frequently with Republicans.

[21] During 2011 redistricting, the Republican-controlled state Legislature sought to gerrymander Barrow out of office by severing liberal Chatham County from his district.

[22] The enacted plan replaced it with more conservative counties in the Augusta metropolitan area, turning the 12th District into a seat that would have been carried by Republican John McCain with 59% of the vote in 2008.

[23] The new boundaries significantly hindered Barrow's reelection prospects, and The Washington Post named it the second-most gerrymandered district in the nation.

He benefited from the lackluster campaign of his GOP opponent, state Rep. Lee Anderson, "whose laid-back and slow-talking demeanor" contrasted with Barrow's aggressive performance on the stump.

[35] The election was controversially canceled by Secretary of State Brad Raffensperger after outgoing Justice Keith R. Blackwell announced his intention to resign from his position before his term was complete.

[36] On May 21, 2024, John Barrow lost the Georgia Supreme Court election against sitting Justice Andrew Pinson by a 10 point margin.

[42] The legislation would have punished any individual who helped transport a minor across state lines to obtain an abortion without receiving proper parental consent.

NARAL Pro-Choice America gave Barrow a 100% rating in 2013, citing his votes against the Pain-Capable Unborn Child Protection Act and legislation intended to make it easier for insurance providers to deny birth control.

"[46] Barrow ran for reelection in 2014 with the endorsement of the NRA Political Victory Fund, which praised him for standing "strong against the Obama-Bloomberg gun control agenda.

He argued that the legislation put "too much of the burden of paying for it on working folks who are already being overcharged" and expressed concerns that the bill would "overwhelm" Medicaid.