Republicans could face same problem with new leader following the movement Donald Trump has spawned

Donald Trump’s Republican rivals in the White House race are lining up to condemn his candidacy after his call to exclude Muslims from America, but even if he were to exit the race, the movement he’s spawned may now simply be waiting for another leader, and one could even be emerging already.

Fellow candidate Senator Ted Cruz, a staunch supporter of the Tea Party’s far-right agenda, has been careful not to speak out against Trump or his supporters so it’s probably no accident that he’s now surged ahead of Trump in a new poll in Iowa, which holds the first-in-the-nation vote to pick the party’s candidate in seven weeks time.

Just hours before Trump made his explosive “policy statement” on the ban because he charged there was “great hatred towards Americans by large segments of the Muslim population”, the poll released by Monmouth University showed Cruz at 24% to Trump’s 19% among Iowa voters.

Cruz has also managed to edge out Ben Carson, who had been in second place but is now down to 13%.

It remains to be seen if Trump’s latest remarks will affect his numbers, similar outbursts in the past have not done so, but this poll marks the first time that he’s lost his coveted front-runner status since entering the race six months ago.

One of the strongest criticisms of Trump’s remarks came from rival Jeb Bush, who called him “unhinged”.

Donald Trump is unhinged. His "policy" proposals are not serious.

— Jeb Bush (@JebBush) December 7, 2015

Then again, why was he not “unhinged’ when he called Mexican immigrants rapists and criminals when he launched his presidential bid?

The answer is essentially down to politics and timing.

Many within the Republican party believed from the beginning that Trump could never beat the presumptive Democratic nominee Hillary Clinton in the 2016 race, but they also knew they had to be careful about moving against him because if he decided to run as an Independent he would likely split the party’s vote and hand the White House to Clinton.

But by waiting so long to speak out forcefully against the millionaire businessman, the party may now simply be left facing the same problem, except with a different candidate.

While Cruz, if he keeps on surging, may appear preferable to Trump, he will still be pressing similar buttons because he knows that’s what he needs to do to woo Trump’s supporters.

And, besides, he probably likes them because the same movement that spawned Trump has also nurtured Cruz.

It’s called the Tea Party and it’s been destroying the Republican Party for over a decade now by pushing it to embrace an agenda that could profoundly harm the party for a generation, and, in the process, American democracy.

Cruz has been embraced by the Tea Party since he was first elected a senator by Texas voters in 2012.

He’s an outspoken supporter of gun rights and once even demonstrated how to cook bacon by wrapping it around the barrel of a gun and then firing the gun so the meat sizzled in the heat.

Fellow Republican senator John McCain once famously dubbed him a “wacko bird”.

But he’s an astute politician and his policies are deadly serious and, like Trump, he seems to enjoy making incendiary remarks about his opponents.

He has repeatedly claimed, for example, that the 2015 international nuclear agreement with Iran “will make the Obama administration the world’s leading financier of terrorism” and calls US president Barack Obama an “unmitigated socialist”.

But, like Trump, the more fiery his rhetoric the more he seems to rise in popularity, and now it’s paid off in the latest poll.

So if Trump doesn’t falter in the coming weeks, his fellow candidates can be expected to take their cue from him and lurch further into ugly political territory where the voters seem to be waiting for them.

The other candidates can, in effect, be expected to out-trump Trump in their rhetoric, tapping into America’s fears about terrorism and national security.

Indeed, the timing of Trump’s latest remarks is probably no accident.

They came just a day after Obama delivered an address from the Oval Office urging Americans not to turn against Muslims in the wake of the terrorist attacks.

So whether this kind of rhetoric comes from Trump today or Cruz tomorrow, it’s probably here to stay for quite some time, and is certain to continue to infect the White House race as it heads into the fast lane.