Wisconsin Governor Scott Walker endorses Ted Cruz for president

The battle in the key state of Wisconsin is heating up before the primary on 5 April

Ted Cruz is edging ahead on the primary polls in Wisconsin (Getty)

Scott Walker, the Governor of Wisconsin and one-time favourite to win the Republican nomination, has announced his endorsement of Senator Ted Cruz one week away from crucial primary voting in his state, thus joining a broadening coalition of forces determined to throw up the buffers to Donald Trump.

Indeed, Mr Walker, who bowed out of the nomination race last September amidst dwindling support and cash, made his announcement in the studios of Charlie Sykes, a very popular conservative radio host in Milwaukee, who has been exhorting his listeners for weeks to reject Mr Trump.

“I am proud to endorse Ted Cruz,” Mr Walker announced on the show, timing his announcement for maximum impact.

Candidates are engaged in a frenzy of campaigning in the state which goes to the polls next Tuesday. Mr Trump will hold a town hall meeting with voters in Janesville in the south of the state later on Tuesday while Mr Cruz has two rallies scheduled in the voter-rich Milwaukee area.

Just as the race in Wisconsin appears wide open at this point, the stakes are sky-high especially for Messrs Trump and Cruz. The fall-out from whatever happens in this state will linger because the next big date for the candidates will not fall until 19 April when New York has its primary.

While Mr Trump has led in most polls in Wisconsin, they have recently suggested that Mr Cruz is closing the gap, in part as he has moved quickly to gather in voters who might otherwise have supported Senator Marco Rubio of Florida who dropped out after losing Florida to Mr Trump. Also important has been the influence of figures like Mr Sykes warning Wisconsinites of the dangers of Mr Trump.

On Monday, Mr Sykes noted in an interview with Politico that an endorsement from Governor Walker would be especially important for swaying the typical Republican in the ring of Milwaukee suburbs who “had supported Walker or Rubio…somebody who would never have imagined they’d be a Cruz supporter, prior to this they might have had a long list of people ahead of him. I think that will help.”

Mr Walker, who led a national movement as Governor to constrain the power of the unions, declined directly to attack Mr Trump as he made his endorsement. “My focus is going to be why I like Ted Cruz,” he said. “To me, I’m all in.”

"I just fundamentally believe if you look at the facts, if you look at the numbers, that Ted Cruz is in the best position by far to both win the nomination of the Republican Party and to then go on and defeat Hillary Clinton in the fall this year," Mr Walker added.

Most alarming for Camp Trump is a recent Emerson poll showing Mr Cruz squeaking by him with 36 per cent of Wisconsin Republicans with the New York billionaire at 35 per cent.