(Also, thanks for pointing out that Libertarians take votes from Republicans - which gives the lie to characterizations like "No Principles Hedonistic Drug Addict Party" (in this thread), which would be a platform clearly more attractive to Rat than Republican voters.)
I would think a substantial portion of the blame for Republican losses lies with Republicans who campaign in such a way as to leave tens of thousands of voters seeing less than a dime's worth of difference between them and their Rat opponent.
True, although for a party that claims to want less government, how can they and their candidates justify that their presence on the ballot stands a good chance in a close election of electing “Biggest Government of All” candidate by a plurality/minority of the vote ? If I were the Dems, I’d want to fully fund Libertarians so they could expressly win these 49-48-3% races. It pays off for them. They probably are. They did in the 2013 VA Governor’s race, which was designed to split the GOP vote and elect the execrable Terry McAwful.
https://www.ourcampaigns.com/RaceDetail.html?RaceID=584602