President Obama touted Obamacare’s supposed benefit Thursday in the hope of distracting attention from Wednesday’s bipartisan House vote that for the first time revealed fissures in congressional Democrats’ lockstep support for his health care law. An unprecedented 35 Democrats bucked the president by voting to delay Obamacare’s “employer mandate,” while 22 Democrats voted to delay its “individual mandate” for one year. Obamacare opponents now have an opportunity to widen the fissures among its supporters.

Starting in 2014, the employer mandate threatens large employers with fines unless they offer health coverage to their workers, while the individual mandate threatens taxpayers with fines unless they purchase a government-approved health plan.

This month, President Obama announced he will delay the employer mandate until 2015. The move was of dubious legality, and widely interpreted as a sign the administration won’t have Obamacare operational by the October 1 deadline. It was also bad optics to cut employers a break without doing the same for families.

House Republicans responded by holding votes Wednesday on two bills. The first would codify the president’s employer-mandate delay, thereby making it legal. That bill passed 264–161. The second would grant the same one-year reprieve to everyday Americans subject to the individual mandate. It passed 251–174.

President Obama threatened to veto the individual-mandate delay. No surprise there: his administration argued before the Supreme Court that Obamacare simply cannot work without that mandate. Moreover, health insurers have hinted that if Congress delays the individual mandate for a year, they would ask Congress to delay the rest of the law, too. Bizarrely, he also threatened to veto the bill that would codify his delay of the employer mandate, and remove any doubt about its legality. (Evidently, Barack Obama thinks only he should be able to amend Obamacare.)

Before Wednesday’s votes, I predicted congressional Democrats are none too happy with their president. The individual mandate is the most hated part of Obamacare. Only 17 percent of Americans support it, and just 12 percent think workers should be subject to it while employers get a pass. The president’s unilateral delay of the employer mandate put House Democrats in a most unwelcome position: either cast a highly unpopular vote to preserve the individual mandate, or reveal a fissure among Obamacare supporters.

The vote tallies suggest my prediction about Democratic discontent was correct. While most House Democrats voted to preserve the individual mandate — which may haunt them in their next election — one in six voted against President Obama on the employer mandate, while one in nine voted against him on the individual mandate. These votes exposed the first fissure in more than three years of lockstep support for Obamacare among congressional Democrats, and are the latest sign that support for the law is fracturing.

Unions are a key Democratic constituency, and many unions that once supported Obamacare are now screaming for Democrats to reopen the law. Last week, the Teamsters, the United Food and Commercial Workers, and UNITE-HERE wrote Senate Majority Leader Harry Reid (D‑NV) and House Minority Leader Nancy Pelosi (D‑CA) that Obamacare “will destroy the very health and wellbeing of our members along with millions of other hardworking Americans.” Obamacare, they wrote, “will shatter not only our hard-earned health benefits,” but is already creating “nightmare scenarios” in which “[n]umerous employers have begun to cut workers’ hours,” leaving workers with “less pay while also losing our current health benefits.” In April, the United Union of Roofers, Waterproofers, and Allied Workers called for “repeal or complete reform” of ObamaCare.

Every implementation glitch that emerges between now and 2014, every complaint ObamaCare supporters hear from unions and other Democratic constituencies will soften congressional opposition to reopening ObamaCare. If the same one-in-nine share of Senate Democrats buck the president on the individual mandate, there would be more than enough Senate votes — 52 — to delay or repeal the individual mandate through the budget-reconciliation process. The more uncomfortable things become for congressional Democrats, the harder it will be for President Obama to veto these measures.

If I were President Obama, I’d want to change the conversation too.