At a press conference about her ongoing grand coalition negotiations with the SPD, the Chancellor was grilled on whether with hindsight she would change her tactics.
Mrs Merkel’s open-door migrant policy saw her popularity take a hit ahead of the election.
And now more than eight weeks after the election, which saw her conservatives suffer losses, Germany remains without a government as coalition talks continue.
In September, Mrs Merkel defended herself, telling reporters: “I cannot see what we should have done differently.”
However in a humbling exchange she has now backtracked on her stubborn defence of the campaign.
She admitted that actually, it would have been better if she had reached an agreement with the CSU on a host of issues, notably immigration, before the election campaign.
Asked whether she stood by her earlier comment, Mrs Merkel said: “I’d rather not repeat what I said then.”
The CDU leader admitted she could have tied up loose ends before the campaign got underway, including coming to an agreement on immigration with the CSU.
Mrs Merkel and her CSU counterpart Horst Seehofer agreed a cap on immigrant numbers shortly after the election, but this had been a point of contention between the sister parties beforehand.
She admitted there were “many issues” between the two parties, “which might have better been solved before the election”.
Mrs Merkel said: “It was the case that there were a number of open flanks, including the disagreement between the CDU and the CSU.
“During the press conference with Horst Seehofer we then spoke about our common set of guidelines and about the fact that there’s a time for everything.
“We can most definitely say that if that time had come before the election it would have been helpful. That’s obviously true.”
It comes as Mrs Merkel is expected to make huge concessions to the left-wing SPD in a bid to keep her grip on power in Germany.
Mrs Merkel must form an alliance that will prop up her Christian Democrat party after her disastrous election results in September.
The SPD leaders have already named key policy demands in a document seen by Reuters – as they know Mrs Merkel is in a difficult position and needs their help.
She risks further disappointing her voters and decreasing her party’s popularity as she battles to form a coalition.
However she maintains the most important thing is to ensure Germany has a “stable government”.