system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is Eric Cantor's defeat such a big deal?

I am not an American, and keep hearing that the GOP is now going to go more 'to the right' as a result. I gotta say...I thought they already went more to the right with the Tea Party a few years back, and their agenda seems more right wing than ever. So is it going even MORE extreme to the right than before? What's going on?
gpt
Generally, incumbents (those already-elected officials running for re-election) have an easy road to re-election. No one in their party really wants to oppose them in their primary because they're already elected, and doing so would rock the boat, and it's an uphill battle for the opposing party's candidate because the guy that's already holding the position typically looks much more suited to the position simply by the fact that he's already holding it. 

Cantor was defeated, not by a Democrat in an open election, but by *another* Republican in his party's primary. This is *huge*, because it means that his party would rather have a Tea Party faction candidate on the ballot than retain an incumbent Republican who is also the House Majority Leader. This indicates that the Tea Party has such momentum behind it (at least in Virginia's 7th district), that the Republicans of said district would rather throw out the enormous advantages that Cantor allows for better representation under another candidate. 

It's another slow step forward in the fracturing of the Republican party - with what end result, none can know.