Like most crises the Depression accelerated an already existing trend, in this case being the steady demise of the Bourbon Democrat.
I think the nomination probably goes to Baker. Garner won't campaign for the job, Ritchie is too wet, too stodgy, too conservative, and tpo southern. McAdoo is haunted by the ghost of 1924, and whoever the Northern Machines settle on (Tammany, Frank Hague, etc) will be too unpopular with the Southern delegates.
The probable result absent FDR is a multi-ballot deadlock that ends up drafting a reluctant Newton D. Baker over Bill Heart's loud objections, who oversees what's effectively a four-year interregnum in the party's evolution(think Grover Cleveland), passes some relief and banking reforms, maybe some tax hikes, and than retires ahead of the real fight for the Democratic Party's future in 1936 (Wagner? McNutt? Barkley?).
I think one of the biggest and most underdiscussed domestic butterflies of a "no FDR" scenario is there being no
Black Cabinet - which is one of the big factors that set the Democrats on course to be the pro-civil rights party. That alone has enormous consequences for the next forty years of American social history and the civil rights movement.
With regards to Civil Rights, I think Democrats are more likely then not going to end up carrying the mantle with or without FDR. The Republican Party had shown zero indication that it would ever take up up the mantle of Lincoln after Harrison fights the GOP's last forlorn stand on it with the Force Bill in the early 1890s. The Democrats had, even before Roosevelt, shown a increasing willingness to court the black vote, with the Wilson campaign of 1912 and efforts by Northern urban machines. Meanwhile Hoover had explicitly run a lily-white campaign against Smith in 1928, with some talk of members of the NAACP going to work on his Al Smith's campaign and had pursued several measures aimed at courting Southern whites at the expense of African Americans.
Fundamentally, any Democrat elected in 1932 is going to pursue some form of relief, if only to appease the big city machines, and some of that relief is going to be doled out to African Americans in Northern cities by newly consolidating Democratic machines looking to cut into the Republican vote with the GOP having taken the African American vote for granted since McKinley abandoned the bloody shirt for the full dinner pail. From there courting African Americans is simply good electoral politics, providing Dems a way to cut into Republican margins in the Northeast and Midwest for (what was then) marginal impacts to party unity.
How relatively conservative would Smith *stay* in office, when faced with economic challenges, when compared with many of his more conservative stances as an outside critic of the Roosevelt Administration?
What states would Hoover still end up carrying in the EC besides his historical Delaware, Pennsylvania, Connecticut, New Hampshire, Vermont and Maine?
Perhaps the line of the Plains states? - From the Dakotas to Kansas, and Minnesota and Iowa? With the rest of the country, industrial midwest, mountain, west coast for Dems?
Or would Smith have a narrower EC majority, like solid south (Hoover loses his upper south inroads from 1928), northeast, with those OTL Pennsylvania and New England exceptions, plus the most metropolitan states only in the midwest, Illinois and Michigan, plus the west coast and New Mexico pushing Smith over the top of the EC while Hoover gets more places in the mountains, plains and midwest/Great Lakes interior?
Putting aside the fact that Smith nomination was very unlikely, as others have noted, owing to both circumstance and personally. I fundamentally don't think Smith would be especially Conservative in office. I think his turn against FDR owes as much to his one time protege's abandonment of him (and going to work with him many of his more liberal minded associates like Frances Perkins) as it does to own conservative instincts.
His 1928 campaign ran on public power development in the Muscle Shoals, on support for collective bargaining for labor, on some form of farm relief, and on public works to relieve suffering among the unemployed, and fundamentally, as a product of the Tammany and Albany Machines, He'll be very attuned to the demands of the party bosses for federal relief and financial assistance to relieve the fiscal burden on major American cities.
As for hypothetical Smith-Hoover rematch? Maybe he loses Ohio and has thinner margins in the Plains states, Hoover probably cracks 40% of the vote, maybe hits the 43-45% that Republicans were stuck at against FDR-Truman until they ran Ike, but he still loses in a landslide.
Baker highlights the flaw in the "edge" case premise simply because he was from outside the old CSA and Border States, and with the thin Democratic bench outside that region, guys like him and FDR were big fish in that small barrel. Highly likely to get shot with the nomination. John Nance Garner, as a Texan, wouldn't have been invited into the barrel.
The supposition I'd always had, and heard, about Baker is that he would have tried to be at least as internationalist and defensist as FDR. On domestic programs, I don't know, but first term, he'd obviously have a mandate for emergency measures, and if dealing with a 2nd dip of Depression or a recession in a 2nd term, he want to react in some effective way and would have several smart people urging him to do so.
How would McAdoo and Baker differ from OTL FDR if significantly at all? Also, any good sources, biographies, etc. on them would be great. IG the other option would be to go with the classic successful Zangara option and have President Garner
Baker, from what I've read was an orate old-school Jeffersonian Progressive who like many Progressives, didn't stick the landing with the New Deal. He thought of himself as thoroughly out his depth with regards to the economic crisis. He disliked much of the New Deal's centralizing measures but also couldn't find within himself to abandon the Democratic Party or join the Liberty League. Baker supported FDR's 100 days but ended up opposing the TVA, the National Recovery Administration, the Agricultural Adjustment Act, and the Robinson-Patman Act and while he supported wide scale federal relief measures he was wary of the possibility of people depending too much on the state.
For a hypothetical Baker Presidency, you have to square his small government inclinations with the fact that he's facing enormous majorities in Congress who do want wide scale relief and large federal programs and his historic unwillingness to break with his party, even during FDR's re-election. I think he ends up signing off a lot of legislation that he privately doesn't support all that much, ends up doing deficit fiancing even if he doesn't want too, and retires ahead of the 36' election owing to poor health and dislike of the Presidency.
Baker has a
biography by C.H Cramer, and there's a
JSTOR article outlining his politics from the 1920s onwards.
McAdoo is one of the Progressives who did stick the landing vis vis the New Deal, so he's probably your best bet for a New Deal without Roosevelt. Garner is somewhere between Baker and McAdoo, a rural Wilsonian who won't turn his nose to federal dollars but was also fairly anti-labor.