In light of the NDP’s recent bump in opinion polling, Eric Grenier looks at how the Liberals fared immediately after the arrivals of their two previous leaders.

When Stéphane Dion became Liberal chief in December 2006, he pushed his party ahead of the Conservatives. Though the Tories hardly budged, the Liberals saw their support increase to 34.2 per cent from 30.5 per cent in polls taken before and after the Liberal leadership convention by the same firms. The bump of 3.7 points came primarily at the expense of the NDP, who dropped 4.8 points overnight.

Michael Ignatieff became interim leader in December 2008 and also increased his party’s support, to 30.5 per cent from 23.8 per cent, a jump of 6.7 points. This was in the highly charged days of the coalition and prorogation, however, so the impact of Mr. Ignatieff’s arrival is somewhat blurred. But in this case, it was the Conservatives who took the hit.

By one poll, the New Democrats actually went into their leadership convention last month tied with the Conservatives, though that had more to do with a drop for the governing party. Similar findings of equality have held over the last few weeks.