Corporate America’s campaign to defend voting rights has moved on to Texas, with dozens of companies including Microsoft, HP and Salesforce calling on local officials to oppose changes that would restrict eligible voters’ access to the ballot.

The open letter on Tuesday from the Fair Elections Texas coalition, which described itself as a non-partisan group, marks the latest in a series of rebukes by large companies of voting bills proposed by Republicans after Donald Trump’s election loss.

According to the independent Brennan Center for Justice, almost 50 restrictive bills have been introduced in Texas, more than in any other state.

The most comprehensive of those would restrict voting by mail, limit early voting hours, increase the likelihood of long queues on election day, encourage purges of voter rolls and heighten the risk of voter intimidation, the Brennan Center warned.

The Fair Elections Texas letter, whose signatories included American Airlines, Levi Strauss and Unilever, pitched ballot accessibility as popular with voters of both parties, good for business and core to companies’ commitments to racial equity.

The letter’s organisers cited findings from a Republican pollster that there was bipartisan support for policies that increase access to the polls, and a study suggesting that the Texas economy could lose billions of dollars if voting restrictions become law.

“We believe the growth of free enterprise is directly related to the freedom of its citizens. Freedom is preserved in our democracy when we hold free and fair elections that protect the fundamental rights of all Texans,” the coalition wrote.

Texas has recently had an influx of corporate investment. CBRE, Charles Schwab and Hewlett Packard Enterprise have moved their headquarters to the Lone Star state, which has no corporate or personal income tax at the state level. Tesla is building its Gigafactory there, and Apple is developing a $1bn campus in Austin.

American Airlines and Dell, two Texas-headquartered companies, had already voiced opposition to specific Republican voting bills that Democrats and civil rights groups allege would disproportionately deter Texas voters from racial and ethnic minorities.

Republicans in the state have pushed back. Dan Patrick, lieutenant-governor, last month said that Texans were “fed up with corporations that don’t share our values trying to dictate public policy”.

In a Wall Street Journal opinion piece last week, Senator Ted Cruz warned “woke CEOs”: “When the time comes that you need help with a tax break or a regulatory change, I hope the Democrats take your calls, because we may not.”

Last month, after companies including Coca-Cola and Delta Air Lines condemned new voting legislation in Georgia, Mitch McConnell, the Republican Senate minority leader, accused companies of “behaving like a woke parallel government”, telling them to “stay out of politics”.

Instead, executives have been looking to band together in coalitions to co-ordinate their response to the estimated 361 restrictive voting bills that have been introduced in 47 states, as well as federal legislation proposed by Democrats to expand voting access.

Companies were “feeling the pushback”, said Daniella Ballou-Aares, chief executive of the Leadership Now Project, which has helped to co-ordinate executives’ responses to the voting rights clash. But many remained committed to countering the “big lie” that voter fraud contributed to Joe Biden’s election victory and were not “scared by the posturing”, she added.

Companies were having “quiet conversations” with legislators in Texas, many of whom were still mindful of companies’ power as investors, employers and donors, Ballou-Aares noted: “There are a handful of Republicans who are very visible and can make up [for lost] corporate dollars with individual donations but it’s not really a viable strategy for most.”