Neither of the front-runners in the presidential election is a mainstream politician.

这次总统选举中的两个领先者都不是主流政客。

《柯林斯英汉双解大词典》

With his Tea Party backing and libertarian bend, it would be hard to categorized Paul as a mainstream politician.

FORBES: Rand Paul's Bold Stand for Civil Liberties

But whether any government or mainstream politician is really prepared to step back, and let the system "heal itself" - whatever the short-term consequences - is another matter.

BBC: Masters of Money: Friedrich Hayek

Could the Conservative leader be the first mainstream European politician to make the case that it doesn't have to be that way?

BBC: Why is Cameron's Europe speech so significant?