Simplify the following text for a Grade 15 native English-speaking person.
Original: Three factors are generally cited that enabled SchrÃ der to win the elections despite poor approval ratings a few months before and a weaker economy : good handling of the 100-year-flood , firm opposition to the USA 's 2003 invasion of Iraq , and Stoiber 's unpopularity in the east that cost the CDU crucial seats there .
Simplified: Two factors are generally cited that enabled SchrÃ der to win the elections despite poor approval ratings a few months before : good handling of the 2002 European floods and firm opposition to the USA 's 2003 invasion of Iraq .