It's a waiting game for Todd Muller who's putting his hand up to lead the National party.

National's emergency caucus is hours away.

There's a huge range of views as to who will prevail, and whether the Bay of Plenty MP will have the numbers to topple Simon Bridges.

The shadow of Judith Collins is seen by many to be key to proceedings.

Newstalk ZB Political Editor Barry Soper told Mike Hosking if Muller is unsuccessful in his quest for the top job, and Bridges retains leadership, he'll go to the back bench.

But he says Muller's future under Judith Collins could be bright.

"If she emerges today, then I think Todd Muller would be very well looked after."

Soper says Simon Bridges has dealt with a lot in his time as leader.

He says Bridges has proved he's a fighter, especially with the Jami Lee Ross debacle.

"I don’t think any leader I can think of has gone through what he has gone through in terms of accusations and survived."

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