Final answer:
As a proslavery advocate, one would feel negatively towards the Republican Party's anti-slavery platform. A legitimate party platform clearly delineates a party's policies on various issues, which both guides the legislative agenda and signals commitments to voters.
Step-by-step explanation:
If you were a proslavery advocate, you would likely feel opposed to the platform of the newly formed Republican Party, given that one of the key tenets of the Republican Party at its inception was opposition to the expansion of slavery.
The characteristics of a legitimate party platform include a comprehensive list of policies and positions on a range of issues, known as planks. For example, party platforms help inform the legislative agenda of the political party if it gains a majority in the House or Senate, and play a critical role in signaling to voters what the candidates stand for.
In forming a platform, parties also aim to appeal to a broad range of voters. The Republican Party in history worked to create a platform that appealed to different factions within the North and ensured that their stance on key issues like the expansion of slavery was clear, while also addressing broader economic and social policies to draw a wider spectrum of support.
The ability of a party platform to articulate clear policy positions and engage citizens in the political process is essential. The platform serves as a guide to what the party's legislative priorities will be and helps voters understand what political beliefs a candidate represents when they run under a party label.