According to 538, the Maine Senate race is the single one of the 36 Senate races this year which has moved the most during the past month and a half. So now, everyone who's been picking on me for claiming this simple fact, can take a deeeeep, deep breath. Maybe I wasn't so shamefully wrong after all, despite your handful or three lame and deeply insulting jokes that I was borderline insane. 
The 538 forecast calculates that Maine has moved 13.1% towards Bellows since September 3, while the vast majority of races have moved less than 5%: http://fivethirtyeight.com/datalab/senate-update-a-lot-has-changed-and-mostly-stayed-the-same/
You neglect the fact that 538 also shows that Collins is ahead by 26 percentage points and that Collins' chance of winning is >99%; essentially rounding up to certain.
I don't dispute with you that the Maine Senate race is unique in the nation. There is no other place where a very popular incumbent Republican Senator is running for reelection in an unabashedly blue state. Since the Democratic nominee is an unknown, it is the only place in the country where the nominee of the majority party of a state is still, in October, introducing themselves to the electorate: this creates the strong movement towards Bellows that can be seen. However, because of Collins' popularity,
this effect is nowhere near strong enough. If Bellows had 42 more days, and gained 13 points during those days, she would still be losing to Collins by double-digits, and she'd barely be doing any better than Allen in 2008. That's how far behind she is. But Bellows doesn't have 42 more days.
Bellows has shown herself to be a skilled politician; she's fundraised very strongly and made leftist groups very enthusiastic about her. When she runs in a Democratic primary for another office in the future, she'll be able to keep that enthusiasm and perhaps win. She has a future in politics ahead of her -- and she is young. At 39, she may even be able to win a Senate seat in the future, when Collins and King are gone.
But she has no chance of defeating Collins.
None at all. Her chance of doing better than 40% are 50/50 at best, and her chance of doing better than Tom Allen in 2008, while not impossible, are very low. She will most certainly lose by double-digits.
Could this be a game changer?
No, that's not how American politics works. I like Bellows but she's going to be slaughtered. She'll do worse than Tim Allen in 2008. You need to accept that.
She has done better in every poll that has come out, so this is not really true. She started out about 40% behind Collins, now she's only 20-something behind. She's at the verge of doing better than Tennant in WV, which was considered being in one of the most competitive of races only months ago.
West Virginia was not considered "one of the most competitive of races" at any point after Capito announced her candidacy. Capito was always going to crush whoever the Democrats put up (though probably not by as much as Collins will crush Bellows).
