WASHINGTON — For weeks, U.S. Sen. Cory Gardner wouldn’t say which of the Republican plans he most favored to repeal the Affordable Care Act.

But a day into the Senate debate on health care, the answer increasingly looks as if the Colorado Republican supports them all.

Gardner on Wednesday backed a controversial and unsuccessful plan to dismantle much of the Affordable Care Act without a ready replacement.

The proposal, championed by U.S. Sen. Rand Paul, R-Kentucky, would cut the federal deficit by an estimated $473 billion over 10 years but leave 32 million more Americans uninsured than under current law, according to the Congressional Budget Office.

What are the odds of the Senate passing legislation on health care this week? Sen. Lindsey Graham: "Call Vegas" pic.twitter.com/eMT4tCujOc — NBC News (@NBCNews) July 26, 2017

Also, premiums on the individual market would double by 2026, according to Congress’ nonpartisan analysis arm.

A two-year window was built into the proposal to give lawmakers time to development a replacement plan.

The idea, however, fell short in the Senate after a 45-55 vote, with seven members of the Republican majority siding with Democrats to defeat it. Among those opposed was U.S. Sen. Michael Bennet, D-Colorado.

Gardner previously expressed reticence about legislation that would do away with the 2010 health care law without a prepared substitute. But on Wednesday he stuck with his party, as he’s done all week.

“As I have said many times, I will do whatever I can to rescue Coloradans from Obamacare’s failures,” Gardner said in a statement. “I voted to repeal Obamacare today because it will put us on a path to put forth a replacement that will bring lower costs and more choices to Coloradans.”

A day earlier he voted in favor of a crucial procedural motion to open debate on health care, a razor-thin win that required a tiebreaker vote from Vice President Mike Pence.

Later Tuesday, Gardner sided with most Republicans in a failed effort to move a version of the repeal-and-replace plan that GOP leaders have debated for weeks. Nine Republicans defected from that idea.