Party switches give the GOP supermajorities in Southern legislatures

Earlier this month, a decision by a North Carolina lawmaker sent seismic shock waves across the state. It was official: Rep. Tricia Cotham of Mint Hill would be joining the Republican Party.

The move by Cotham, who was elected last year as a Democrat to represent Mecklenburg County's House District 112 by a 59-41 margin, handed the Republican Party a legislative supermajority able to override vetoes by Democratic Gov. Roy Cooper. Progressives decried the switch as a betrayal and raised concerns about the future of abortion access and LGBTQ+ rights in a critical swing state. Research has shown that Democrats who switch parties tend to vote more conservatively; Cotham previously supported abortion rights, even talking openly about her own abortion on the House floor in 2015, but since the switch has been evasive about whether her abortion stance will change. 

Cotham's switch is part of a larger recent trend in Southern politics. Last month, Louisiana state Rep. Francis Thompson, the longest-serving Democrat in that legislature, also switched parties, giving the Republicans a supermajority able to override vetos by Democratic Gov. John Bel Edwards. Thompson's colleague Rep. Jeremy LaCombe followed suit shortly thereafter, further strengthening the supermajority.

And last week, West Virginia House Del. David Elliott Pritt joined the GOP only a few months after he was elected as a Democrat over a Republican incumbent by a 52-48 margin. His switch leaves the 100-member West Virginia House with only 11 Democrats. It also strengthens the GOP's trifecta control of the state, whose governor, billionaire coal mogul Jim Justice, also switched from the Democratic to the Republican Party while in office.

Between 1989 and 2020, more than 400 state legislators switched political parties, according to a study by political scientist Boris Shor of the University of Houston. Most of these switches have occurred in Southern states and have been from the Democratic to the Republican Party. The trend reflects broader historic party realignment and partisan change in the South, which saw vast numbers of white voters move from the Democratic to the Republican Party following the passage of civil rights legislation in the 1960s.

"We've gone from a one-party Democratic South to a two-party South to at least a Republican-ascendant South, which we have today," said Chris Cooper, a professor of political science and public affairs at Western Carolina University.

Seeking more clout

Christian R. Grose is a professor of political science and public policy at the University of Southern California who has published research on legislative politics and party switching. While he said party switching is not that common, it can equate to more political clout for elected officials who change their affiliation to the majority party.

"If you look at Louisiana and West Virginia, I think that was partly what might have been driving those cases," he said. 

Cotham and Thomas have both said that their switches were prompted by the Democratic Party no longer aligning with their views, a statement echoed by the West Virginia Republican Party Chairperson regarding Pritt's switch.

"The modern-day Democratic Party has become unrecognizable to me and to so many others throughout this state and this country," Cotham said at a press conference announcing her switch. She also complained about her treatment by fellow Democrats angered by her absence from a vote to override of Cooper's veto of a bill loosening gun restrictions, which as a consequence was passed into law. 

Grose called Cotham's case "a bit of a head scratcher," especially because her district does not trend Republican. The legislator hails from a well-known family of Democratic leaders in her county, and she previously served in the state House for a decade as a Democrat.

"Presumably she's been promised a lot of goodies to switch parties to become a Republican in terms of her institutional position," he said. "She's going to have a lot of sway … If the Republican Party is unified, she's basically the decisive vote to overturn a governor's veto, and so I think there's institutional reasons that would explain why she's doing it."

Cooper also said it's possible Cotham has her sights set beyond the state legislature. Among the incentives for party switchers is when politicians' districts are redrawn to be friendlier to the opposing party — something that Cooper doesn't see happening with Cotham's suburban Charlotte district.

"It is extremely unlikely it will be a Republican district," Cooper said. "So what does that say for her? I think it says that perhaps she doesn't see her political future as being in the General Assembly. Perhaps she sees her future being statewide office."

The electoral consequences

Cooper sees some of the recent party switches as part of a larger story about an increasing convergence of ideology and partisan identity. In the late 1970s, for example, 1 in 5 Democrats called themselves a conservative, he said. Now, that isn't the case.  

"The old, white, blue dog Democrats are loosely an extinct species in the South," he said.

The recent party switches in West Virginia and Louisiana involved some of the few remaining Democrats representing deep red Republican areas. 

But switching has consequences when it comes to subsequent elections. Party switchers, particularly those in more electorally competitive areas, often face challenges not just in the general election but also in their primaries from opponents who criticize them for being inconsistent or for lacking trustworthiness.  

Grose noted that, when voters lack other information about a candidate, party affiliation is a huge predictor of how they make decisions. But in the case of party switchers, voters will likely know about the switch, and it will shape their response.

"For a Republican voter, does her becoming a Republican trump the lack of trust that may be engendered by switching parties?" he said. "And for a Democratic voter, do you vote for the person you've known, who maybe you did trust that now you may not trust anymore, because they have switched parties?"

However, Grose's research has also found that the penalties suffered by party switchers tend to be more short-term. 

"If you survive after switching parties, you'll stick around for a while," he said. "But a lot of times that first election is where those trust allegations come in, and the attacks from both the primary and the general election challengers can really start to hit."