[Homer_J_Simpson]

The National Union Convention – 2
The Republican National Convention – 2
Triple Murder a Hoax – 2
Disaster at Sea-Six Lives Lost – 2

[BroJoeK]

The National Union party is now known as the Constitutional Union party, and it's usually forgotten in the narratives about Lincoln's Republicans versus Douglas Northern Democrats and Breckenridge Southern Democrats.

The Constitutional Union party was the old Southern Whig party and was vital in Whig presidential victories of 1840 & 1848.
When Whigs collapsed, mid-1850s, some Southern Whigs became Democrats, some became American Know-Nothings and by 1860 those in Border States coalesced as the National / Constitutional Union Party.

Mostly ignored today, they actually won more states and electoral votes than Douglas' Northern Democrats.
And they were critical to keeping Border States in the Union in 1861.

They demonstrated that, at least outside the cotton-South, there were Southern majorities who put National Union ahead of radical Democratic party pro-slavery ideology.