William Freehling, The Road to Disunion: Secessionists Triumphant 1854-1861 (New York: Oxford UP, 2007), pp. 137-40

Northerners in Kansas deplored the Lecompton Constitution, with or without Article Seven [which permitted slavery; the document also banned free blacks from the state and allowed only male US citizens to vote], and they doubted that referendum votes on Article Seven would be fairly counted. So they shunned the Lecompton polls on December 21. Their absence allowed the southern minority, by a vote of 6266–567, to affirm Article Seven and seek admission to the Union, with constitutional protection for future slaves to join the lonely 200.
On January 4, 1858, the Topeka free soiler crowd held its own referendum on the Lecompton Constitution. Topeka voters chose among the constitution with Article Seven, the constitution without Article Seven, and no constitution at all. No constitution at all secured 10,226 votes to 162 for any Lecompton Constitution. Combining the Lecompton and Topeka tallies, 6428 Kansans voted for the Lecompton Constitution and 10,793 against it.

Stephen A. Douglas did not need this mathematical proof to repudiate the Lecompton referendum. A month and a day before the Topeka crowd thumpingly rejected the Lecompton Constitution, he descended on the White House to denounce the sellout of Popular Sovereignty. No witness recorded the curses exchanged, but the final epithets seem clear enough. Buchanan declared that like President Andrew Jackson, he would destroy any Democratic Party senator who dared to oppose a Democrat's administration. [Mr. President,] spat back the senator, [General Jackson is dead.]

The insult inaugurated a showdown between two irreconcilable northern warriors. Where Buchanan considered Popular Sovereignty a treasured weapon to keep slavery controversy out of Congress, Douglas considered local selfgovernment itself the treasure. Where Buchanan, a narrowly practical lawyer, demanded that the letter of a legal process be legitimate, Douglas, a charismatic seer, insisted that the spirit of democracy be sustained. Where Buchanan had to have his southern support, Douglas had to have his northern constituents. The Illinois senator, up for reelection in 1858, would be finished as a national politician if he lost at home. He could never win in Illinois if he endorsed Lecompton's desecration of the spirit of Popular Sovereignty.

By consistently refusing to trample on Popular Sovereignty, Douglas served as both the midwife of the Kansas-Nebraska Act and a slayer of its Lecompton fruits. In 1854, Southern Democrats had insisted that Douglas would no longer be Douglas unless he authorized Kansas/Nebraska settlers to decide on their local institutions. In 1857–58, Illinois constituents insisted that Douglas would no longer be Douglas if he allowed the Kansas minority to enslave the majority. If the Lecompton Constitution [is to be forced down our throats,] Douglas responded, he would [resist … to the last.]

Considering all that Buchanan had to resist—Douglas's revolt, the Topeka referendum's proof that most Kansans loathed the Lecompton Constitution, the inclusion of the notorious Article Seven in an already iniquitous democratic swindle (so most Northerners considered everything coming out of Lecompton)—considering in short how tainted was his cause in the North, this powerful political infighter swung a remarkable percentage of Northern Democratic members of the House of Representatives, fully 60 percent, behind the Lecompton Constitution. That topped the percentage of Northern Democratic congressmen that Douglas had rallied behind the Kansas-Nebraska Act, barely over 50 percent. This continued Northern Democratic appeasement of the South illuminated again why the minority South had long controlled the majoritarian republic: The Democratic Party was the nation's majority party, and the South was the party's majority section. Buchanan never forgot that reality. Douglas now defied it.

Unfortunately for Buchanan, Yankees had grown obsessed with stopping the Slave Power minority from ruling the northern majority. Stoppage demanded obliterating the appeasing Northern Democrats. Where eighty-one Northern Democrats had served in the Kansas-Nebraska House, only fifty-three Northern Democrats remained in the Lecompton House. Fifty percent of eighty-one Northern Democrats had been enough to pass the Kansas-Nebraska Act by eleven votes, even with thirteen Southern Whigs voting no. In contrast, 60 percent of fifty-three Northern Democrats could approve the Lecompton Constitution only if all but one Southerner voted yes.

…. Thus did the Lecompton finale illuminate how minuscule minorities' initial concerns ballooned into unmanageable majoritarian crises. The tiny fraction of Missouri slaveholders who lived near the Kansas border, comprising a tinier fraction of the South and a still tinier fraction of the Union, had demanded their chance to protect the southern hinterlands. Southerners in Congress (unlike potential settlers in the countryside) flew to the aid of their fighting outpost, both in the Kansas-Nebraska Act and in the Lecompton proceedings. Both times, Northerners loathed the southern minority for demanding that the white majorities, whether in Kansas or in Congress, kowtow to Slave Power tyrants. Southerners loathed Northerners for calling them tyrants. The mutual loathing had helped doom one national party, imperil the other, and threaten the minority's control over majoritarian Union. That control would snap over Lecompton unless almost every southern House member rose against the Yankee majority.