Sen. Lisa Murkowski, R-Alaska, recently made headlines when she told her state’s Legislature she would not support an Obamacare repeal bill eliminating the law’s Medicaid expansion.

Apparently, there are a lot of short-term memories in Washington. No one reminded Murkowski that she already voted to repeal Obamacare’s Medicaid expansion when in 2015 she voted for a reconciliation bill that would up being vetoed.

The difference between now and then? Whereas everyone knew Obama would veto any repeal effort, with President Trump now in office, repeal might actually pass.

Apparently, that’s giving some senators heartburn. Reports are drifting out of the Senate about many Republicans—all of whom voted for the 2015 repeal bill, except for Sen. Susan Collins—drawing lines they suddenly will not cross.

For some members of Congress, it seems, the trigger is a little bit harder to pull when they’re firing with real bullets.

Before they delay the repeal effort into irrelevance, these members need to remember a few key things.

First, a continued delay in repealing Obamacare means a continued delay in keeping promises to voters. Republicans ran—and won—on repeal. This is a promise that needs to be kept.

Second, the rest of the Republican agenda hinges on the imminent passage of Obamacare repeal. Why? The rules and procedures of Congress—the Senate, in particular—require sequencing.

Congress has to pass a reconciliation vehicle for the fiscal year 2017 budget, which contains Obamacare repeal, before they can move onto the fiscal 2018 budget, which will likely be comprised of major tax reform. In the meantime, Congress must also deal with a looming debt ceiling this summer, as well as a government funding deadline in April.

If Congress is going to repeal Obamacare, they need to do it. Now.

Third, while Congress continues to dither, Obamacare continues to harm American families. Congressional hemming and hawing over the possible fate of the insurance market post-repeal is akin to rearranging deck chairs on the Titanic. The insurance companies have already said they are prepared to handle repeal without too much disruption to the marketplace.

Moreover, it is the state of Obamacare—not some vague anxiety about what Congress may or may not do—that is causing insurers to exit the marketplace. In fact, even the nonpartisan Congressional Budget Office has suggested that repeal of Obamacare would be less disruptive than repair.

More importantly, however, Obamacare is crumbling, which means that members of Congress aren’t helping anyone by delaying repeal. Rather, by continuing to delay repeal, this Republican Congress is becoming complicit in perpetuating Obamacare’s harm onto the rest of the country.

Consider just a few facts about the state of today’s health care market. The average nationwide premium on the individual market has gone up 99 percent in the period between 2013 and 2017. For families, they’ve risen an eye-popping 140 percent.

How about all those insurance options we were supposed to have under Obamacare? Nope. About 70 percent of counties in the U.S. have only one or two options for insurance. And forget the 20 million extra people who were supposed to be covered by Obamacare. Revised estimates put the figure at half that.

In what is about to be the third month of a Republican-controlled Congress, this state of affairs is not OK. It’s even worse when one considers that Congress has a repeal bill they already passed in 2015 that they could simply cut, paste and pass again.

The Congressional delay to repeal Obamacare may have, to some, been understandable. But it is now inexcusable.

The 2015 Obamacare repeal bill got at the guts of Obamacare, targeting the major components of the law for elimination. It also contained a two-year phase out of the law, allowing Congress time to deliberate on—and build bipartisan consensus toward—what replacement should look like. Most importantly, though, it passed both the House and the Senate.

The country elected this Congress to repeal Obamacare and reform the health care system. Should this Republican Congress continue to delay—or to pass a repeal short of what they did in 2015—they risk owning the worst domestic policy issue in a generation.

The longer Congress waits to repeal, the more excuses senators like Murkowski will come up with to duck voting for a bill they’ve already supported. As everyone in Washington knows, delay is the first step toward doing nothing.

Obamacare repeal should have started yesterday. The good news is, it can start tomorrow. Congress has passed—and can pass again—the 2015 repeal bill, but only if members stop giving excuses to delay it.