WASHINGTON (AP) -- Paul Ryan's mentors have included some of the biggest conservative names of recent decades, among them Jack Kemp and Bill Bennett.

But the ideological roots of Mitt Romney's vice presidential running mate sprouted from Ryan's small-town Wisconsin upbringing. And his outlook and career were nurtured by a libertarian college professor and by a devotee of supply-side economics who is now top aide to another rising Republican star, Florida Sen. Marco Rubio.

Ryan emphasizes individual responsibility, small government and unfettered economic markets. As chairman of the House Budget Committee, he pushed a spending plan through the House that reflects those values, trimming tax rates, cutting spending for low-income programs and government generally and reshaping Medicare.

Democrats have made his budget a campaign target, calling it extreme.