State lawmakers defy governors in a Covid-era battle for power.

State lawmakers across the country, most of them Republicans, are moving aggressively to strip the powers of governors, often Democrats, who have taken on extraordinary authority to limit the spread of the coronavirus for nearly a year.

In a kind of rear-guard action, legislatures in more than 30 states are trying to restrict the power of governors to act unilaterally under extended emergencies that have traditionally been declared in brief bursts after floods, tornadoes or similar disasters. Republicans are seeking to harness the widespread fatigue of many Americans toward closed schools, limits on gatherings and mask mandates as a political cudgel to wield against Democrats.

Lawmakers frame the issue as one of checks and balances, arguing that governors gained too much authority over too many aspects of people’s lives. These legislators are demanding a say in how long an emergency can last, and insisting that they be consulted on far-reaching orders like closing schools and businesses.

But governors respond that a pandemic cannot be fought by committee. They say that the same Republicans who politicized the science of the pandemic last year, following former President Donald J. Trump in waging a new battle in the culture wars, should not be trusted with public health.

Last April, when governors in all 50 states declared disaster emergencies for the first time in the country’s history, support for their initial stay-at-home orders to slow the virus’s spread was generally bipartisan.

But that soon evaporated as Mr. Trump, obsessed about the economy in an election year, played down the virus. Supporters echoed his dismissal of health experts and defied governors who filled the federal leadership vacuum to manage the pandemic — especially Democratic governors whom the president took to insulting, issuing cries to “liberate” states like Michigan.

Across the country, lawmakers in 37 states have introduced more than 200 bills or resolutions this year to clip the emergency powers of governors, according to the lobbying firm Stateside, which focuses on state governments.