In the far southwestern corner of Alabama lies the 1st congressional district, a heavily conservative area where voters will head to the polls Tuesday in what's shaping up as the latest test of the tea party's electoral heft.
Nine Republicans are vying for the nomination in the special election to replace Jo Bonner (R), who gave up his congressional seat this year to accept a high-ranking position in the University of Alabama system.
Byrne, a Democrat until 1997 and a onetime chancellor of the Alabama Community College System, is running as a conservative Republican who will fight corruption and wasteful spending in Washington. "In Washington, I'll cut Obama's waste so we can start creating jobs," he says in a campaign ad.
In what was seen as a blow to the GOP establishment, Byrne lost a 2010 GOP runoff to Robert Bentley, once a little-known state legislator and now the state's governor. Byrne was at odds in that race with the state teachers union, which he once called the "single greatest impediment to quality education in this state." The battle would prove to be costly, as union efforts contributed to his defeat at the hands of Bentley.
Back for another bite at the apple, Byrne now faces a crowded field of opponents. Among the eight others running for the GOP nod are a handful of very conservative candidates jockeying for second place in a competition for a slice of the electorate that is not part of Byrne's base: the tea party.
"I don't think he has great deal of support from the tea party," said Alabama Republican Party Chairman Bill Armistead of Byrne.
Armistead said he sees four candidates competing for the the tea party vote Tuesday: Real estate developer Dean Young, who lost to Bonner in 2012; Wells Griffith, a former Republican National Committee aide who has the support of Rep. Paul Ryan (R-Wis.); Quin Hillyer, a conservative writer backed by Rick Santorum; and state Rep. Chad Fincher.
Griffith released one of the most memorable ads of the campaign, a spot in which he throws a copy of the Obamcare bill into the trash, a strategy reflecting the conservative tilt of the 1st district.
Under state election law, if a candidate does not cross the 50 percent threshold, a runoff between the top two finishers will be triggered in November. Most observers expect a runoff, and for it to include Byrne. Who would he face? It's an open question. But this much is clear: Whomever it is would have to defy the odds to win.
"It's not a lock for Bradley Byrne that he will win the runoff, but I think it's his to lose," Armistead said.
"Byrne wants Young or Fincher in a runoff," said Republican strategist Bill Buchanan, whose firm has polled the race. "Young is incredibly polarizing and doesn't have much of a base outside of Baldwin County, and not a very strong one there. Fincher is nearly non-existent in Baldwin, not nearly as strong as needed in Mobile County, and he doesn't have access to money."
It would take a united effort and desire on the part of the tea party — not to mention a candidate they can united behind — to defeat Byrne. It's not clear either will be there.
Buchanan said the tea party has not been a real force in the state in recent elections. "Since 2009, they haven't exerted themselves in any campaign," he said.
What's more, the contours of 2010 — which was a banner year for the tea party and candidates running with anti-establishment messages — when Byrne lost, are not the contours of 2013. The tea party's influence has broadly faded in some ways.
In other ways, though, the conservative wing of the party remains a force. It's worth noting that the Alabama campaign is unfolding against the backdrop of a national fight for the heart and soul of the Republican Party. Conservative Republicans in the U.S. House — many of whom were elected in 2010 — successfully pressed GOP leadership to back a bill to defund Obamacare that ups the risk of shutting down the federal government at the beginning of next month.
Turnout is expected to be pretty low Tuesday, adding to the unpredictability of the race. A pair of Democrats and an independent are also competing for the seat, but none of them are believed to have any real chance of winning a district Mitt Romney carried with about 62 percent of the vote in 2012.
Especially in off-years with few instances of voters casting actual ballots, special elections receive a great deal of attention as observers and strategists look for clues about the larger environment. As a result, they are sometimes overread. So it's important to view this Alabama race for what it is: A contest in a heavily conservative district with several competing interests. And in the end, it will probably say nothing about the head-to-head battle between Republicans and Democrats heading into 2014.
But with the tea party lined up behind a slate of candidates running against a Republican who doesn't have much support from the far right, the race could say something about the GOP, which is engaged an ongoing effort to find its identity following a disappointing 2012 election.
Polls close at 7 p.m. central time Tuesday. Stay tuned to Post Politics, where we will have results.
Updated at 3:47 p.m.