National is facing an internal battle over how best to return a centre-right government under MMP. Former Cabinet Minister Maurice Williamson argues that with National polling around 30% while holding a large number of electorate seats, extra party votes for National will not produce extra MPs. He suggests National voters strategically give their party vote to ACT or New Zealand First to maximize the right-wing seat count. However, party heavyweights John Key and Chris Bishop reject the strategy, urging voters to stick to two ticks for National to ensure a stable government. Meanwhile, polling scenarios from the Sensible Sentencing Trust suggest a small 3% shift in party votes could materially alter the election outcome. Duncan Garner breaks down the parliamentary arithmetic, evaluates Labour and National's campaign launches, and sits down with Maurice Williamson to debate the numbers.