Suppose the Democrats nominated a deeply unispiring conservatrive or Bryan got the nod and scared people. Any thing else?
They already had nominated an uninspiring conservative - Alton B Parker in 1904. He got 38% ofthe vote, which if repeated in 1912 would be more than enough to win a three way race.
As for Bryan, there's no reason for him to scare people in 1912 any more than in 1896, 1900 or 1908 - in all of which he won more votes than Wilson in 1912.
In 1912, all the Democrat -
any Democrat - needed to win was to be still alive on Election Day. TR might have an outside chance on the Republican ticket, though given the party's unpopularity it could be no more than that. Any other way, forget it.
If so what happens. IN FORMAL terms he would not havea party in Congress.
Would things change/
In any terms at all he wouldn't have a party in Congress. A few progressive Republicans in the west might climb aboard, but the regular Republicans and all Democrats would be against him. Think John Tyler or Andrew Johnson with a bit more personality.