Even those in eastern Ukraine do not want to split apart to join Russia, for the most part:
Although I wonder how good the survey is for Crimea residents given that they are within the loving embrace of Mother Russia, now.
Putin may be pushed by domestic factors to invade eastern Ukraine. Putin has stoked irredentist nationalism that is bolstering his popularity, but having gotten on that horse he may have trouble getting off of it without taking more territory for the restored glory of Mother Russia.
The fact that most Ukrainians--even those in the east where Putin says they are being repressed--don't want to secede from Ukraine may make invasion the only way to make good on his nationalist credentials.
For all of Russia's Spetsnaz-organized revolts in eastern Ukraine, the Russians haven't been able to set the conditions for complete Russian control short of invasion the way the Russians did in Crimea.
Further, as the Spectator article notes, without all the ethnic Russians (and actual Russians) of Crimea within Ukraine, the percent of the "Russian" element of Ukraine drops to 30%. That makes it unlikely that Ukrainian domestic politics will see the rise of another pro-Russian candidate free to pursue closer ties to Russia alone.
I'll also note that with Ukraine no longer hosting a Russian military base at Sevastopol--since Russia has conquered the Crimea--Ukraine is no longer barred by NATO rules from joining NATO.
So with the uprisings unable to simulate a popular revolt or to keep the Ukrainian security forces from operating against them, the Russians may be faced with the option of giving up on eastern Ukraine (and maybe their objective of getting acceptance for taking Crimea involves making the Russian threat to eastern Ukraine seem more real than it is) or sending in conventional forces.
Russia might even try what I thought they could attempt while the Ukrainian military was largely absent--send in Interior Ministry troops to "restore" order in major eastern cities currently suffering violence (from Russian-instigated uprisings, of course). This keeps the Russian army out of the fight for the time being, and might be seen as a compromise between invasion and going home.
A botched Sunday referendum by those separatists in eastern Ukraine could compel Putin to decide on a course of action defined by invasion or sending his army back to their bases.
