PORTLAND, Ore. -- Demonstrators concerned about the health care crisis held a rally in downtown Portland, calling for a single-payer health care system.

The group Health Care for All Oregon joined representatives from the Democratic National Committee and the Oregon Working Families Party to oppose any Republican plan to pass health care legislation.

President Donald Trump is calling on the Senate to get things done this week, and a vote on health care is scheduled for Tuesday in Washington D.C. But it still wasn't clear Monday afternoon whether the vote would be to simply repeal Obamacare, or to repeal and replace it with a GOP plan.

More: The Senate isn’t saying what’s in the health care bill — but still plans to vote on it Tuesday

Travis Nelson, a registered nurse in Portland, spoke during the rally at Terry Schrunk Plaza.

“We cannot afford to have 22 million people lose their health care," he said. "We cannot afford the cuts to Medicaid and Medicare, so that’s why we are here. We want to see more people covered. We want to see lives saved. And we want single payer health care for everyone.”

Lisa Stiller, who organized the rally, said about 1.13 million people in Oregon have received insurance through the Medicaid expansion or subsidies through the ACA exchange in 2017. She says the only reliable fix for our health care system is a single-payer, government-run health care program.

“We do believe it’s important to make this statement to say we really believe the only true answer to our health care crisis is an expanded and improved Medicare for all system.”

Related: How the revised version of the Senate health care bill would affect you