Giron's seat has a substantial Hispanic population, is working class Democrat, and was carried by President Obama by 22%. Democrat's can trot out all the usual non-presidential year low turnout by the base arguments they like but, however they slice, it Giron's defeat was astonishing.
It was even more astonishing given the massive amount of money outside groups and individuals like New York City Mayor Bloomberg threw at it in an attempt to influence anti-gun legislation. Bloomberg gave $300,000 personally, and the total money available for the Dem's was reported at $3 million, a huge difference to what was available for the Republican effort-a 6-1 deficit. The Anti-recall forces also ran 2,346 television adverts to only 144 for the recall campaign.
Looking to 2016 Colorado, may be the key factor in the Electoral College in a tight campaign. President Obama won it twice after the state had been reliably Republican previously, and the influx of Hispanic voters would have played a significant role in changing the state to lean Democratic. It is perhaps highly significant then that Giron's electorate with its Hispanic/blue collar "Reagan Democrat" element had such a massive swing to the GOP.
If the Democrat's are seen to be anti-gun in this western state, and the Republicans run a team that includes a pro-gun populist, a libertarian as regards marijuana use and an Hispanic person or one who has Hispanic support, then the state could swing back and with it the election.
Studies have shown that if the Reagan Democrats/Perot voters had turned out for Romney he could have won in 2012, the Colorado result shows that Democrats will vote for Republican issues if those issues are seen to affect them directly.
By financing the anti-gun Democrats in Colorado Bloomberg and his progressive allies may have inadvertently given the GOP a strong issue to put in front of exactly the voters they need to win over in 2016-conservative Democrats and Western Hispanics
If in 2016 the economy has not recovered and is in fact in a parlous situation then history shows, as with John McCain in 2008 it doesn't matter who the candidate for the party holding the presidency is, no matter how prominent and capable, or who the challenger is, no matter how unknown or judged incapable, there will be a landslide to the challenger.