original: This took the republic by surprise, especially because the SPD was below 25% in polls at the time.
simplifications: This took the republic by surprise since the SPD was under 25% in the polls. Republic was surprised because the SPD was below 25% according to polls. This took the republic by surprise. The SPD was below 25% in polls at the time. This surprised the republic since the SPD was currently below 25% in polls. It took the republic by surprise,  because the SPD was below 25% in polls at the time. This surprised the republic because the SPD was polling below 25%. This took the republic by surprise. They were surprised because the SPD was less than 25% in polls. This was a surprise to the republic especially because the SPD was below 25% in polls at the time. The republic was surprised because the SPD was below 25% in polls at the time. This surprised the republic, especially because the SPD was below 25% in the polls at the time.