VANCOUVER—The first Liberal federal budget has twisted the Trudeau knife further in the wounded New Democratic Party. The first budget of the new government is a big hit with elite centre left voters, a moderate success with populist or struggling groups, and leaves conservative groups infuriated. As a result, the Liberals are up, the NDP has declined even further from their election night and the Conservatives are treading water. Despite more short-term pain for the NDP, the party still retains a slightly larger pool of available voters than the Conservatives. The challenge is to find issues that have both a populist and a left-wing appeal.