Factors affecting voting in Congress

Members of Congress vote frequently on legislation and legislative amendments. They also hold a range of other important votes, including constitutional amendments, initiation of military action and, in the Senate, ratifying presidential appointments.

When they do vote, members of Congress might be voting on budgets, amendments to bills, final passage of bills, bills from conference committees, constitutional amendments or — in the Senate — on treaties or appointments made by the president. They will probably be rushing to the floor to cast their vote, having just broken off a committee hearing or a meeting with constituents or staff.

Congressional politicians are subject to a number of pressures that determine how they vote.

· Public opinion/constituency Representatives must take into account public opinion or run the risk of being voted out of office. Congressmen and Senators are subjected to frequent elections, which provide public accountability due to the threat of removal. It can be argued that this factor is more important in the House, as elections to the House take place every two years, compared to six years to the Senate. However, separation of powers means that there are strong levels of representation in both chambers, creating an individual mandate for each politician. People are likely to vote for a certain candidate due to their individual policies rather than because of their party label or party leader. In 2009 several Democrats switched their position, dropping their support for Obama's Affordable Care Act, after meetings with constituents and rising opposition to the bill. The New York Times stated that ten moderate Republicans opposed the Republican plan to repeal this act in March 2017. Some of these moderates represent districts which voted for Clinton in 2016. Politicians in the House and the Senate are clearly more accountable to public opinion than their own president.

· Party/party leaders 

Unlike the in UK Political party not the main determinant of voting in Congress. For some members, on some issues, it may be the most important determinant. A  party vote — sometimes occurs in Congress when the issue is a contentious, ideological matter, such as civil liberties, taxation, gun control, abortion or school prayers. Party voting is much more common in recent years. Unlike the UK Parliament, the parties have few ‘sticks’ or ‘carrots’ to encourage party voting. Sticks such as the threat of de-selection do not work in a system in which voters decide on candidates in primary elections. Carrots such as jobs in government do not work in a system of ‘separated institutions’, in which posts in the executive and legislature do not overlap. So leaders also have limited use of patronage power with promises of committee chairmanships or membership to induce politicians to vote a certain way. No Republicans voted for Obama's stimulus budget in 2009, arguably due to partisanship rather than an ideological belief that the economy should self-stabilize and the government should not interfere. However, the fact that local opinion led 11 southern Democrats to vote against Obama's 2009 economic stimulus package suggests that public opinion has a greater impact on the way Congressmen vote.

Party discipline is weak

But partisanship in Congress has increased

However, being members of a party, representatives are pressured to vote according to the majority party view. There is a sense of belonging to a party that encourages politicians to vote together.  

·    Caucuses There are many factions within Congress, often called caucuses. Some are based on ideology (such as the conservative Blue Dog Democrats). Other factions are based on social characteristics, such as the congressional black caucus, which has approximately 40 members. While it is dominated by Democrats, it is officially non-partisan: Mia Love, the first Republican black congresswoman, is part of the group. Yet others are based on economic interests and are not set along party lines, such as the Congressional Steel Caucus containing approximately 100 members who mainly represent districts with steel manufacturers. These groups often vote together on legislative issues.

·    Interest groups and lobbyists . Make direct contact with members as well as with their staff. They attempt to generate public support for their position. They make visits and phone calls, provide evidence to committees, organise rallies, demonstrations and petition drives, and engage in fundraising and campaigning. Money raised is used to fund politicians who support their cause and to seek to defeat those who do not. Some interest groups, such as the AFL-CIO (American Federation of Labor and Congress of Industrial Organizations) and the AARP (American Association of Retired Persons), also have large, active memberships, so members can mobilise to create the threat of removal of members from Congress. Members of Congress, once they leave Capitol Hill, can command a much higher salary within such an organisation.


Revolving-door syndrome  

Are US Interest Groups good for democracy? 

Pressure from the Administration

Most  legislation voted on in Congress has been initiated by the administration. One of the most useful functions of the cabinet for a President is to lobby congress in support of the president's legislative programme. Cabinet members — the heads of the 15 executive departments — have take a keen interest in the passage of legislation affecting their policy areas. So cabinet members and their staff as well as the White House itself  and agencies— keep in contact with members of Congress through phone calls as well as meetings in an attempt to persuade them to cast their votes in certain ways. Often the White House gets involved through the Office of Legislative Affairs as well as directly by the president.

The relationship between the presidency and Congress

Personal beliefs

On certain votes, House or Senate members may vote according to their own personal beliefs. Issues such as abortion, capital punishment, taxation (increases or cuts), federal subsidies and defence spending are likely to bring a member’s own personal philosophy to the fore. There are, for example, members of

Congress who will never vote for a measure which might be linked to abortion- e.g Stupak Pitts Amendment

All Politics is Local- Constituency pressure

Speaker Tip O'Neil famously noted that in Congress ' All politics is local'. Members of Congress are far more aware of how their individual votes will be received in their state or district than MPs in the UK Parliament.  In 2020 Republican Congress members were very aware that Trump had considerable popular support and were very hesitant to object to claims that the election had been stolen.  Interest groups will publicise the voting records of individual congress memebers in oredr to apply pressure.


Congress operates on a 'you help me and I'll help you' basis. Congressmen do deals across congress to garner support for their bills or have amendment inserted in legislation. The president will do favours in the same way by inserting 'pork' in to draft bills to reward support in Congress. In this way bills gather amendments as the price for gathering support. Pork Barrel