The collapse of the Bülow block meant that for the next few years the government had to rely mainly on the Black-Blue block, the reactionary-clerical coalition. The result was the reconstitution of a united left liberal party, the Fortschrittspartei, and the foundation of the Hansabund (see p. 116). Even the National Liberals were forced to the left. Their gradual adaptation to the political mass market and reduced reliance on notabilities had made them more responsive to their predominantly big-city voters. But when it came to asking their supporters to cast their votes for a SPD candidate on the second ballot, National Liberal and even Progressive voters often preferred bourgeois solidarity. An alignment left of centre from the National Liberals to the SPD was therefore as fragile as the Bülow block had proved to be. Intellectuals like Naumann talked of a coalition from Bassermann to Bebel. Ernst Bassermann was the leader of the National Liberals in the Reichstag. But even in Baden such a coalition proved short-lived. There the BlackBlue block was even stronger than in Berlin and forced liberals and socialdemocrats together. Contrary to the line laid down by the Bebel leadership, the Baden SPD, following their Bavarian counterpart, collaborated in passing budgets, from which their followers stood to benefit. After a while the Baden National Liberal voters turned against a policy of collaborating with those whom they considered their natural enemies. To keep the SPD united Bebel had to pay regard to his left wing, and to keep the National Liberals together Bassermann had to keep in with his right wing. It was a long way from the SPD left to the National Liberal right. The events culminating in the fall of Bülow therefore showed the German political system in a state of comprehensive immobility. The Kaiser could not remove Bülow while he enjoyed parliamentary support, but he could have maintained him in office, had he wanted to, even after his finance reforms had been defeated. He was still free to choose his successor. Party combinations remained fragile and the parties preferred their freedom to choose allies to forcing the chancellor of their choice on the monarch. They paid for their unity and dogmatic purity with the price of immobility and they were in hock to the interests and lobbies to which they were linked. The Centre party provided a kind of buffer zone for the system. It limited the gains the SPD could make in working-class areas that were predominantly Catholic, but in the Reichstag it could ally itself with the Conservatives.