08/24/2010 09:31 am ET | Updated May 25, 2011

Arizona Senate Primary: John McCain Emerges As Clear Front-runner Over J.D. Hayworth

PHOENIX (AP) - Two years after his tough loss in pursuit of the White House, Arizona Sen. John McCain faces voters again Tuesday.

This time he's poised to fare better.

Once considered 1 of the Senate's most vulnerable incumbents, McCain is now the clear front-runner against conservative challenger J.D. Hayworth in Arizona's Republican primary.

Hayworth, a former congressman and talk-radio host, has given an alternative to conservatives frustrated with McCain's famous willingness to buck his party and work with Democrats on issues like campaign finance, immigration and climate change.

But McCain, who has never lost an election in his home state, has fought hard to cut into Hayworth's credentials as a conservative outsider.