MADISON, Wis. – With their Senate colleagues still in hiding, Democrats in the Wisconsin Assembly began introducing a barrage of 100 amendments Tuesday to try to stymie the Republican governor’s plan to strip unionized public employees of most of their bargaining rights.

Both houses of the GOP-controlled Legislature convened shortly before noon amid noisy protests outside the state Capitol that began more than a week ago in an epic showdown that is being watched nervously by organized labor across the country.

The Senate was unable to take up the union measure when 14 Democrats skipped town last week, denying the chamber a quorum. But Assembly Speaker Jeff Fitzgerald pledged that his chamber would approve the bill this week, despite the blizzard of Democratic amendments.

Turning up the pressure on the Democrats, Gov. Scott Walker warned that state employees could start receiving layoff notices as early as next week if the bill isn’t passed soon. The layoffs wouldn’t take effect immediately — existing union contracts could forestall them for weeks or months — and Walker wouldn’t say which jobs he would go after first.

“Hopefully we don’t get to that point,” the governor said in a statement.

Borrowing the strategy pioneered by President Franklin D. Roosevelt, Walker took his case straight to the voters Tuesday evening with a speech from his Capitol office that he called a “fireside chat.” With protesters drowning out his message as it was played over monitors in the rotunda, Walker calmly laid out his case for the bill, saying it was needed to balance the state’s budget now and into the future.

“It certainly isn’t a battle with unions,” Walker said. “If it was, we would have eliminated collective bargaining entirely or we would have gone after the private-sector unions.”

Walker warned of “dire consequences” if the Democrats don’t return soon to pass the bill, saying up to 1,500 state workers could be laid off by July.

One of the missing Democrats, Minority Leader Mark Miller, delivered his own response from Illinois.

“The only action available to us to slow this down and allow democracy to work was to take us out of the Capitol,” he said.