Republican Jeb Bush¡¯s new campaign ad ridiculing Donald Trump as a ¡°germophobe¡± and Democrat-in-disguise is just the start of what will be a bigger onslaught, signaling a more aggressive stance by the candidate, Bush advisers said on Wednesday.

Some confidants of the former Florida governor have been seething for weeks at Trump¡¯s taunts and attacks on Bush. They have been urging the campaign to shift from the cautious approach that has distinguished Bush¡¯s early months as a candidate.

The two men are among 17 candidates for the Republican nomination in the November 2016 presidential election.