Cruz wins Wisconsin, invigorates anti-Trump camp

Texas Senator Ted Cruz scored a commanding victory over Donald Trump in Wisconsin's presidential primary on Tuesday, putting the Republican frontrunner on notice that his march to the nomination is not a done deal.

Meanwhile the Democratic frontrunner Hillary Clinton also crashed to defeat against upstart Senator Bernie Sanders. He has now won six of the last seven Democratic contests and can bolster his claim to be a viable alternative standard-bearer to the former secretary of state.

But the Wisconsin results are almost certainly more damaging for Trump, the brash billionaire who stormed to the fore last year but has suffered campaign trail setbacks in recent weeks with a series of controversial comments about abortion, NATO and nuclear weapons.