The Senators won 23 of their final 31 games in the regular season, helped in large part by rookies Mark Stone and Andrew "Hamburglar" Hammond. The win on Saturday means Ottawa will play either Montreal or Tampa Bay in the playoffs.
No matter who the Senators play, the excitement after an improbable playoff berth resonated over Twitter.
Ottawa Mayor Jim Watson wasted no time in chirping John Tory, mayor of Toronto. A former politician also celebrated.
Senators owner Eugene Melnyk and the team's players chimed in soon after the final horn sounded. For many on the young Ottawa team, it's their first chance at playoff hockey.
Former Senators' captain Daniel Alfredsson shared his thoughts, too.
As for fans, joy and surprise were key themes after the win.