US Presidential Election 2016: Former Republican President George Bush joins campaign trail to support his brother Jeb as Donald Trump steps up rhetoric
US Republican candidate Jeb Bush has been given a much-needed boost, after his brother George W Bush joined him on the campaign trail in South Carolina.
While George W remains a controversial figure around the world, he is extremely popular in South Carolina, where much of the electorate is made up of veterans.
George W joined Jeb at a rally on Monday, ahead of Saturday's primary election, where he said: "I have seen in my brother a quiet conviction. This is a serious election, for a serious job, so please welcome a serious and thoughtful candidate."
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"There's no doubt in my mind Jeb Bush has the experience and the character to be a great president," the former president said, further jesting that South Carolina should support the candidate with "the most opinionated mother" in Saturday's primary.
Bush made the intervention after Jeb came fourth in the New Hampshire primary and sixth in the Ohio primary.
On Saturday tensions rose between the Republican candidates during a televised debate. Donald Trump said George W's record was terrible, accusing him of lying about the reasons behind the Iraq war, which he said destabilised the Middle East.
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"George Bush made a mistake," Trump said.
"We all make mistakes. But that one was a beauty … They lied. They said there were weapons of mass destruction. And there were none."
Jeb had defended his family during the debate, saying he was proud of his brother's accomplishments at building security, while his dad is the "greatest man alive in my mind". He added Trump had "the gall to go after my mother. My mother is the strongest woman I know".
This race could be closer than the previous two primaries – won by Ted Cruz and Trump – as South Carolina senator Lindsey Graham, who quit the presidential race and is now backing Jeb Bush, has said: "The Bush name is golden in my state."