The latest MP expenses show a massive jump in National MP Todd Muller's spending on travel and accommodation in recent months.
The Bay of Plenty MP will go head to head with opposition leader Simon Bridges tomorrow for the National Party leadership in an urgent caucus meeting at Parliament.
Muller spent $34,528 over the past three months - the second highest spender in the caucus after Simon Bridges.
As party leader, Bridges always spends the most - this time $37,183 - but Muller's big spend suggests he has been trying to raise his profile around the country.
The third highest spender among National's ranks was National's Rotorua MP Todd McClay at $27,118.
Regional MPs often incur higher expenses as their role requires more travel.
However, Muller's spending from the quarter prior was about $11,000 less than what he spent over the last three months.
When asked about this his expenses, Muller said as National's agriculture spokesperson he "attended a large number of meetings around the country on a range of issues particularly the government's freshwater reforms."
Ahead of tomorrow's leadership vote, Muller has told the caucus he will be speaking with each of the MPs individually.
MPs on both Team Muller and Team Bridges have said tomorrow's vote could go either way.