This discussion may contain spoilers!
I started and finished the episode in one day...admittedly with one or two hints (subtle hints!), but mostly figured out myself. Now, I'm going to try to help everyone else.
Q: How do I...
A: Once again, general hint: Consult Max first. Listen closely to what he says, even if he makes no sense, and something may give you a clue.
Q: How can I get past the bouncer?
A: You can't just muscle your way through. You need a distraction.
Look around the white house yard for something that might be helpful.
You may, and by "may", I mean "probably will", have to leave the white house to find the solution.
If you could get him to answer the phone...
Look at the phone to the right of the door, then go back to your office and call the white house. Put superball on hold.
Q: Chuckles won't let me beat up the president...and ever since I learned about the wiretappings I've REALLY wanted to!
A: Explore the white house.
See if there are any other rooms to explore.
Try to go into the war room, and Chuckles will throw you out. "Governor" Whizzer will be escorted in. Okay, so I didn't answer the question this time.
Q: Whizzer is inside. Now what?
A: Chuckles doesn't seem to like it when people go into the war room.
If you can get someone ELSE to go in there, it'll provide a nice distraction.
The president, the monkey that he is, can't understand Whizzer.
He seems to need an interpretter to do the work for him.
Be sure to talk to Whizzer privately, and cover all the topics.
Adventure games are always about exploiting people's weaknesses for no reason...when someone has balanced a rock perfectly, you knock it over. Etc.
Tell the president that Whizzer is thirsty.
Then tell the president he needs to use the war room. In the ensuing cutscene, Chuckles leaves.
Q: What can I beat up Bush...I mean the president with?
A: What did you use in Episode 1?
It should be out on the lawn. Although I'm very surprised you didn't find it yourself.
Q: Max doesn't seem to be able to hold up very well in the election...
A: How do REAL presidential elections work?
Are they just one-upping THEMSELVES, or...
mud-slinging their opponents?
Don't worry about Max, just make Lincoln look like a horrible candidate. There are 4 key topics: Family values, nuclear waste, taxes, and religion/education.
Q: The voters just accept his little campaign slogan for every topic.
A: If he's saying the same thing each time...where's the phrase being prompted from?
There are a bunch of cue cards to the right of Lincoln. Hope he's a regular Ron Burgundy.
You'll need to find some new signs for Abe, and he'll read them off.
Q: Where can I find signs?
Wherever something is televised...where have you seen cameras recently?
It's actually quite close by.
There are cue cards in the president's office.
Well, you often see signs on the street...
Dead End and One Way are nailed on, but maybe there are some less adhesive ones?
You don't want to be mean and steal things; where can you find excessive signs stacked over each other?
Get an army recruitment poster from the alley to the left of Sam and Max's office.
Abe Lincoln's signs aren't colorful enough.
Who is the MASTER of colors?
...and reminds you of L. Ron Hubbard?
Hugh Bliss has a sign next to his bookshop.
Q: ___________ won't sell it to me.
A: Time to pull a Superball on him. The agent, not the ball.
Hugh Bliss likes to stroke his ego for magic tricks.
Tell him to do a magic trick. When he disappears, grab the sign.
Q: How can I use the signs in the right order?
Let's start with "Two wrongs do not make a right."
Which subject concerns two "wrongs?"
With that sign up, ask Lincoln about religion and education.
American people hate when taxes...
Go up! But more importantly, they hate the fact that the GOVERNMENT takes them.
Use the "give me all you've got" poster with the taxes question.
Where to dispose of nuclear waste?
Think. Where would you LEAST like to see that stuff put?
On your own doorstep.
Use the "free home delivery" sign for the nuclear waste question.
Q: I just need one more scandal to push things over the top.
A: Sybil, your local journalist-turned-witness-turned-etc...should be good at scandals.
Ask her about her dating service...but more importantly about herself.
Usually people campaigning for president have literature to hand out to people.
Take a flyer from under Abe Lincoln, and give it to Sybil.
Q: Abraham Lincoln refuses to call Sybil.
A: There's no way you're going to convince him to do something against his wife.
Maybe you can just try to fool Sybil.
Think back to the beginning of the episode; BEFORE the opening credits.
Use the organic listening device on Lincoln, let him give his speech, then take the bug and bring it back to the office, where you can use it on the phone to call Sybil.
Q: I'm not exactly sure what to say to Sybil...
A: I'm not sure if I can give such subtle hints on this one. These ones are going to be outright answers.
I, Abraham Lincoln, am that man.
This is a date to be remembered.
I stand here at the steps of the white house.
The time to act is now.
Q: OH GOD. MAX IS PRESIDENT. Oh, and there's a giant statue rampaging through town.
A: It's time to make use of your new presidential powers.
Check out the neat stuff on Max's desk.
Unfortunately, you STILL can't get into the war room. And an ICBM would be the PERFECT thing to stop Lincoln!
There are two things stopping you from entering the war room. 1. The guard who still takes orders from Chuckles, and 2. It's not actually war.
Q: How can I start a war?
A: I know what I'd do. Invite a bunch of dictators to my home and use naughty language on them.
Hey! There are already governors sitting in the office.
They're angry at each other over Mt. Rushmore, but not quite over the edge.
You need them to tell each other what they truly feel.
Give Whizzer the Bosco-Tech Truth Serum.
Q: Where am I going to get a hundred million dollars?
A: Come on. Max is president! Doesn't that give you SOME jurisdiction over how money is spent?
The presidential budget is on Max's desk.
Hmmm...it seems like it only lets you allocate money to HISTORICAL monuments.
Let's randomly decide to visit Sybil.
Ask her to demonstrate her carbon dater. Her office becomes a historical monument.
Q: How can I make Bosco's a historical monument?
A: Don't worry about HIM yet. Sybil is in deep financial trouble.
Now that her office is a historical monument, allocate some pocket change to her with the presidential budget.
With her financial troubles gone, Sybil will leave the office, leaving you with the carbon-dating machine.
Now it's time to find something old in Bosco's.
Hmmm...what item's age has come up each episode?
...And in this one? Try talking to Bosco.
Use the carbon dater on the weenies. Then allocate a hundred million to him to get the...vodka?
Q: This time, Superball REFUSES to budge. And there's no phone in sight.
A: Jesus, does that guy EVER take a day off?
It's time to use your secondary presidential power: Changing the official date!
Which day looks like a good holiday for certain people?
Change the date to secretary's day.
Hmmm...he's not a secretary, sir.
Tertiary presidential power, go! MAKE him a secretary!
Take the ribbon from Max's desk and put it on Superball.
A: Yeah, I dunno. The animation budget probably got taken from anime shows (in which the characters never move) and was given to this one, which needed a good way to use it.
Q: YAY NUKES...but I can't select Abe Lincoln as a target.
A: What's that on the bottom of the screen?
There needs to be a homing beacon on something for it to be nuked.
Where could you take one from?...Check the monitors!
Which one is an easily accessible location?
Take the one from Bosco's, which is right behind the "Buy 1 get 1" sign. Then use it on Lincoln in the high-speed statue chase.