A head to head comparison of the Delaware 2012 General Election gives us an idea of the break down of the voters.    

Barack Obama received 242,547 (59%) votes, beating Mitt Romney who gained 165,476 (41%) by 77,071 votes in Delaware.

Barack Obama won 2 counties whereas Mitt Romney won 1 county in the total of the 3 counties in the State of Delaware.

Presidential General Elections

During the 2012 General elections, over 122M total number of votes were cast. Barack Obama got 62,614,654 (62.6 Million) over Mitt Romney's 59,141,654 (59.1 Million). He won the popular vote by 3,472,979 (3.4 Million). His victory at the State of Delaware (with 242,547 votes) represents 0.4% of his popular vote victory. The remaining 49 states contributed to the remaining 99.6% popular votes victory.

Top 3 Counties in Primary Elections vs General Elections

All Candidates (General Elections)

These 3 counties play an important role in these Primary elections. If a candidate, can get a sizable majority in the largest county (New Castle), it becomes very difficult to win majorities in the smaller counties without voter outreach and increased voter participation in them.

Top 15 Counties Comparison in Primary Elections vs General Elections

General Elections
Barack Obama

General Elections
Mitt Romney

New Castle and Kent, two of the larger counties, voted in favor of Obama giving him a 89k vote advantage. Sussex, another larger county voted in favor of Romney giving him a 12k voter advantage in that county. However, it was not enough to catch up, making Obama gain an upper hand in the State of Delaware.

Related References: 2016 Delaware Primary Election Story, 2016 Delaware General Election Story 2020 Delaware Primary Election Story, Story 2020 Delaware General Election Story