In the latest polls the two parties who want to reopen Nord Stream (AfD and BSW) have 25%. Many Germans (I'm one of them) still shy away from these parties and grudgingly vote mainstream, because obviously Nord Stream is just one of many issues:

https://www.wahlrecht.de/umfragen/

So I'd estimate that in an honest poll to reopen Nord Stream and protect it militarily you'd easily get 60% in favor. That aligns with the 61% of Germans who are against delivery of Taurus missiles:

https://www.economist.com/the-economist-explains/2024/03/12/...

That 61% is in danger of being ignored yet again if Merz becomes chancellor in Feburary next year, though it will be Trump who is in the driver's seat by then.