US House Majority Leader Eric Cantor loses seat in shock upset

WASHINGTON - In a stunning political upset, House Majority Leader Eric Cantor, the chamber's number two Republican, was ousted by a conservative Tea Party challenger, US media reported.

With 220 of 243 precincts reporting, Virginia election officials said David Brat, an economics professor, was leading Cantor 55 per cent to 45 per cent.

Should the results hold, Mr Brat will have pulled off the most unexpected American political upset of the year, if not several years, sending shock waves through the Republican House leadership ahead of November's mid-term congressional elections.

The Republican establishment has largely fended off the challenges of candidates backed by the anti-tax, small-government Tea Party in a series of primary elections over the last several weeks. But Mr Brat's victory is sure to re-write the Republican playbook as the party seeks to field the most viable candidates possible in the general elections in November.