No abstract

W"Jf 7"hy, given a strong presumption of success, do some presidential nominations fail? Of 1,464 \/%/ important nominations from 1965 to 1994, less than 5% failed. Ninety-four percent of failures f f were rejected or withdrawn before reaching the floor, suggesting that opponents are most effective during prefloor stages. We propose a theoretical framework based on the notion that policy entrepreneurs pursue their goals within the context of a presumption of success. Logit analysis tends to support the theory that entrepreneurs can alter the presumption of success and defeat a nomination if they (1) identify negative information about a nominee to provide a rationale for changing the presumption and (2) expand the conflict through committee hearings and the media. Presidential resources-high public approval and efforts to signal that the nomination is a high priority-increase the chances of confirmation. Contrary to previous research, divided government has no independent effect on the fate of nominations.

The virtual disappearance of moderate and cross-pressured members from the US Congress is analysed in this article. There were substantial numbers of these partisan non-conformists in both parties and in both chambers until the early 1980s when the middle began to shrink. This trend continued and accelerated in the 1990s. Partisan non-conformists disappeared through replacement and conversion. When moderate and cross-pressured members left Congress, their replacements were much more likely to be mainstream partisans in the 1980s and 1990s than they had been in earlier decades. The occurrence of some type of conversion (a shift towards the party's ideological mainstream or a party switch) is also much more common in recent decades. We present evidence that the shrinking middle in Congress resulted from electoral changes.

Presidential-congressional relations scholars have long debated whether the president is more successful on foreign policy than on domestic policy (Wildavsky, 1966). The debate has focused on differential success rates between foreign and domestic policy and whether the gap has narrowed over time. This focus, however, neglects an important dimension of Wildavsky's argument. Wildavsky also argued that presidents should dominate Congress in foreign policy. Hence, the thesis predicts high levels of success on foreign policy as well as differences between foreign and domestic policy. Looking at the trends in success on foreign and domestic votes, we observe that whereas the difference between foreign and domestic success rates shows up consistently for minority presidents, the absolute level of support on foreign and defense issues has declined since the second Reagan administration. Analysis of opposition party base behavior reveals that foreign policy voting has become considerably more partisan.

We analyze the relationship between public approval and presidential success in Congress using time-varying parameter regression methods. Cues from constituency, ideology, and party dominate congressional vote choice, so the effect of public approval of the president is typically marginal. Because the strength of these primary cues varies through time, the effect of public approval on presidential success should also be time varying. Analysis of conflictual roll-call votes from 1953 through 2000 using the time-varying Kalman filter reveals that the effect of public approval on presidential success is marginal and changing through time. These models assume that the time variation is a stochastic process, and finding time-varying relationships may indicate model misspecification. Our theory, however, suggests that this time variation depends on a systematic factor-partisanship. A better specified model that allows systematic parameter variation confirms that the level of partisanship conditions the relationship between public approval and presidential success in Congress.During the four decades since he first proposed it, Richard Neustadt's (1960) proposition that the president's standing with the public affects his ability to achieve legislative success has gained wide acceptance. Presidents, legislators, pundits, and a host of Washington insiders routinely report that the president's public approval provides leverage with Congress (see, e.g., Edwards 1997). Several studies testing the relationship with quantitative data also report evidence