The m/o in AZ in 2010 was Democrats spending money to portray a libertarian as the true conservative in order to bleed-off votes from the Republican candidate and Iraq War veteran Jesse Kelly and thus re-elect the Democrat, Rep. Gabby Giffords, who went on to get shot by a lunatic with libertarian ideas named Jared Loughner. To add insult to injury, liberals nationwide then went on to blame her shooting on Republicans and the Tea Party.
I reported on this in early January 2011, here, showing a mailer for the libertarian paid for by the Arizona Democrat Party.
Now it turns out the same strategy was used in Montana in 2012 to boost the libertarian candidate as the real conservative, funded by liberal money, in order to bleed-off votes from the Republican Rehberg and re-elect the Democrat Senator Tester.
Propublica has the in-depth story, here.
Everyone thinks the Republicans are the stupid party when in two recent elections it's the libertarians who got played for fools and tools. But the Republicans really are the stupid ones for thinking an alliance with libertarians isn't just possible but natural when far more often than not libertarians view themselves as successful when they prevent Republicans from getting elected, as they themselves say here (h/t Chris).
We know whose side they are on. Libertarians are natural liberals, not conservatives.