I think for California, 696 is an obvious answer to this question:
They last won an event in 2007 at San Diego, but they’ve won a whole list of other awards since–3 quality, 3 industrial design, 1 excellence in engineering, 1 innovation in control, 1 gracious professionalism, and 1 WFFA, in addition to making finals at IE 2013. They’ve also been a captain/first pick at every event since 2011, attended IRI in 2013, and build beautiful machines every year. They’re also really nice people and always willing to answer questions every time I’ve talked to them.
(also according to my friends I’m obsessed with symmetrical / powdercoated / color coordinated robots as well as palindrome numbers, so it’s hard to get much better than 696)
Other strong contenders:
649: won SVR in 2010, and have made finals at SVR again in 2015 but haven’t managed to get another win, despite putting up strong robots each year. In 2016 alone they made semis at both CVR and SVR, won excellence in engineering and imagery, and were finalists at Calgames.
3256: they won Sac their rookie year (2010), then made finals at Sac and SVR 2012. Despite winning Calgames 2015, they haven’t been able to win another official event, although they have gotten an impressive number of other awards since their last win: RCA x2, EI x1, dean’s list x3, WFFA x1, industrial safety x4, entrepreneurship x4 (including 3 in one year), and finalists x2.
I’m probably missing teams, and I’ll come back and add them when I think of more. For norcal in particular, there have been very few unique teams winning regionals, although there is an increasing number of teams challenging that.
In the past 4 years, there have been 3 norcal events per year, coming to 12 events or 36 slots on winning alliances–but there have only been 19 different teams. On captain/1st pick slots it’s even more drastic: 8 teams vs 24 slots, and for captain/1st picks for the past 3 years, it’s 5 vs 18.
Put another way: from 2013 on, there has only been 1 norcal event that didn’t have either 1678 or 254 on the winning alliance. From 2014, that number is zero. They make up for 16 of the 24 winning captains/1st picks since 2013, 14 of 18 from 2014 on. This data graphed (with multiple winners colored):
(they’d probably also say I’m obsessed with streaks. But seriously, this is crazy)
*All stats are for official events only
*The 8 capt/1st pick winners (team (# wins at norcal regionals)) are 1678 (9), 254 (7), 971 (2), 118 (2), 973 (1), 840 (1), 2489 (1), and 3189 (1). The first 5 are winners from 2014-16.
Hopefully this year. Gunning for it hard.