I hope the tea party is dead or its influence has greatly diminished. The tea party turned many Republicans into obstructionists instead of compromisers. They were hell-bent on opposing the Obama agenda, even on issues where they could have found common ground. I'm a relatively moderate Republican and I believe the Tea Party greatly damaged the party. Don't get me started on the Freedom Caucus
I cannot stand the freedom caucus, but I am sympathetic to the at least the motivations that sparked the tea party. What killed the tea party was that it was hijacked by ideological extremists on a whole host of issues.
That being said what came to be called the tea party in early 2009 was already a present force in 2007. You had incumbents losing primaries over the immigration issue in early 2008 and whole base revolt over that in 2007, throw the bailouts into the mix and you have a populist rebellion gainst both party establishments and against both Wall Street and Washington DC. There was anger at the corruption and incompetence under the GOP and at that point, changing out unpopular scandal plagued candidates had actually proven its value. In 2006, Republicans lost several seats because of scandal plagued incumbents, but held on to the Alaska Governorship, solely because an outsider candidate defeated the corrupt incumbent in the primary.
The problem was many of the politicians who rode this wave were ideological libertarians on the economy and very far right on social issues. This led to the obstructionism in Congress.