More than 2.5m ticket requests have been received from 128 countries at the halfway stage of the month-long application phase.
Applications for tickets will be accepted until midnight on March 31.
The 2008 UEFA European Championships will take place in Austria and Switzerland between June 7-29.
Christian Mutschler, Euro 2008 tournament director, Switzerland, said: “In the league table of applications from fans, Switzerland has opened up a clear lead, followed by Austria and Germany.”
