Republicans hold a huge advantage in post-2020 redistricting and are poised to redraw over twice as many districts than Democrats

• A new study from the Brennan Center paints a grim picture for the next round of redistricting.
• Congressional districts are redrawn every 10 years when the census is completed.
• The process will be "the most challenging in recent history," according to the report.

A new study from the Brennan Center found significant hurdles lawmakers will face when redistricting this year and in 2022, with Democrats facing a substantial disadvantage to Republicans.

The study from the non-partisan law and policy institute described "a tale of two countries," with anti-gerrymandering reforms making district redrawing more fair in some areas while others remain under partisan control.

Key victories in state-level races allowed Republicans to retain substantial influence over districts will be redrawn in vast swaths of the US.

Democrats were already facing an uphill battle after 2010, where they suffered monumental losses nationwide in state legislatures as Republican turnout surged during the height of the Tea Party movement.

In 2020, Democrats fell short in many states where regaining majorities in state legislatures would have given them more control over how House districts would be redrawn, as Insider's Grace Panetta reported back in November.

The Brennan Center study found that Republicans will have complete control of the new boundaries for 181 districts compared to a maximum of 74 for Democrats, though the final numbers could fluctuate once the census is completed. A report in The Atlantic with exclusive access to the same report put the GOP number at 188.

Democrats have a potential silver lining stemming from reforms undertaken in some states, where control over redistricting was transferred from the legislature to either the courts or non-partisan commissions. Republicans also lost super majorities in the key swing states of Wisconsin and Pennsylvania.

Another critical state for Democrats in the Electoral College, Michigan, switched from legislative redrawing to using an independent commission. There might also be a more favorable map in Ohio, where voters approved a ballot initiative for a vague set of reforms.

Redistricting for US Congressional districts is a sprawling pastiche, making shifts in broader dynamics hard to pin down.

The Brennan Center report described the next round as "the most challenging in recent history," even before the pandemic compounded issues facing an already weakened census operation from the Trump administration.

However, the overall playing field remains tilted against Democrats, and they will have to wait until 2030 for another shot at turning the tables.