When that "bubble" is at minimum one quarter of the country, maybe you need to reconsider who is in the bubble here.
it's not "at minimum one quarter of the country", the turnout was 52.56% of registered voters, so its at minimum 22.94% of 52.56% of 18 million, which is 11% of the total population of Romania.
This person went really quickly from unknown to anyone not into politics, to incredibly popular within a targeted media bubble and still unknown to anyone unfamiliar with that bubble.