On Tuesday a huge majority of MPs lent their support to gay marriage. However those campaigning against the Bill admit only that they lost that battle, not the war.
Following the 400 to 175 Commons vote, several overseas news organisations including CNN and Al Jazeera were quick to report that Britain had made it legal for gay people to marry. But the Bill is still a bill. And is not yet law.
The Marriage (Same Sex Couples) Bill will next be examined line by line by a committee of MPs. Opponents, including the Coalition for Marriage (C4M) campaign group, hope to regroup after the second reading retreat and substantially change the legislation at this stage with a view to eventually killing it.
"Tuesday was Dunkirk," a C4M spokesman told the Huffington Post UK. "There will be lots of amendments given the strength of the rebellion."
The cross-party committee, which includes many pro-gay marriage MPs such as Labour’s Chris Bryant and shadow equalities minister Kate Green, also includes leading anti-gay marriage Conservatives David Burrowes and Tim Loughton.
Green expects MPs to offer amendments designed to ensure the European Court can not force a religious body to conduct a same-sex marriage and to allow teachers to refuse to teach gay marriage if it conflicts with their religious beliefs. But she is also wary of anti-gay marriage MPs attempting to blow the Bill up in committee.
"There is real danger of people looking for an opportunity wreck it," she told HuffPost UK.
And Lib Dem Julian Huppert, who is supporting an amendment to expand civil partnerships to include mixed-sex couples, says he expects many "dinosaur" Tories to try and wreck the Bill.
Civil partnerships for heterosexual couples is also being pushed by some anti-gay marriage MPs. But this is seen as an attempt by them to restrict marriage to religious ceremonies while the state just conducts civil partnerships.
"What we want is equality, marriage should be open to people regardless of their gender," Huppert said. "Some old school Tories are mostly trying to cause trouble and want to do things from stop marriages from happening."
Opponents of the Bill are also hopeful it will get bogged down in the House of Lords if it gets out of the Commons.
However as Paul Waugh at Politics Home and Isabel Hardman at the Spectator have pointed out, the arithmetic and experience of past votes appear to scupper the notion that the red benches are stuffed with anti-gay peers.
The 221 Labour peers and 90 Lib Dems combined easily outnumber the 213 Conservatives, even if all the Tories decided to vote against the Bill. Labour expects the dissent on its benches in the Lords to be small, similar to that in the Commons, where 22 Labour MPs voted against the Bill. Throw in the majority of the 178 cross bench peers and there appears to be a progressive majority in the upper House.
But C4M questions how well the Labour and Lib Dem leaderships know the minds of their own peers – expecting their Lordships to take issue with the quality of the legislation as well as the principle of gay marriage. "It is rushed legislation that is full of holes," a spokesperson said.
If last Tuesday was Dunkirk, anti-gay marriage MPs, peers and campaign groups see next Tuesday, the first day of committee stage, as D-Day.